ACHD Echo Protocols

Basic Report Template for Adult Congenital Echocardiography – Normal heart

Situs solitus, levocardia, atrioventricular & ventriculo-arterial concordance.

Normal right ventricular size and systolic function.

Normal right atrial size. The interatrial septum appears intact.

The pulmonary valve functions normally.

There is * tricuspid regurgitation. The estimated right ventricular systolic pressure is *mmHg if right atrial pressure is *mmHg.

Normal left ventricular size and ejection fraction. Biplane EF = %. Normal wall thickness & diastolic filling parameters.

Normal left atrial size.

The aortic valve is trileaflet and functions normally. Normal aortic root & ascending aorta. There is normal flow through a left aortic arch.

The mitral valve is structurally and functionally normal.

No evidence of pericardial effusion.

CONCLUSION

Normal LV size & ejection fraction, EF *%.

Normal RV size & systolic function.

Estimated RVSP *mmHg.

No significant valvular disease.

Supplementary ACHD Echo Acquisition Protocol for

Atrial Septal Defects

The following protocol for echo in adult patients with atrial septal defects (ASDs) is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to unrepaired & repaired ASDs.

Background

• ASD represents one of the most common congenital heart disease lesions in adult patients.
• It is not uncommon that it remains undiagnosed until adulthood since patients may remain asymptomatic or only mildly symptomatic for a long time.

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Diagram showing different types of ASDs

1. Sinus venosus (SVC type)
2. Secundum ASD
3. Primum ASD
4. Sinus venous (IVC type)
5. Unroofed coronary sinus ASD.

Diagram adapted from Popelova et al

• The secundum ASD – located within the region of the oval fossa – is by far the most common type (approximately 80% of ASDs).
• The “primum ASD” – located near the crux of the heart – accounts for approximately 15% of ASDs. It belongs to the group of atrioventricular septal defects (partial AVSD or partial AV canal) and is typically associated with AV-valve abnormalities and will be addressed in the atrial ventricular septal defect protocol.
• The sinus venosus defects are located at the regions connecting atrium and the caval veins.
  • The superior sinus venosus defect is much more common (~5% of ASDs) than the inferior one (<1%) and is typically associated with partial (sometimes complete) drainage of the right pulmonary veins to the SVC and right atrium.
  • Sinus venosus defects can be difficult to visualise on transthoracic echo, so often transoesophageal echo is necessary.
• The unroofed coronary sinus is a rare form of ASD, characterised by a communication between the coronary sinus and the left atrium. It is almost always associated with a persistent left caval vein draining to the roof of the left atrium.

Common associations

• Right ventricular volume overload
• Elevated pulmonary artery pressure
• Secondary tricuspid regurgitation
• Right atrial dilatationAnomalous pulmonary venous connection (sinus venosus and secundum defects)Persistent left SVC (unroofed coronary sinus)

Treatment

Defect can be closed either via:

• Surgical patch
• Direct suture (if small)
• Percutaneous occluder

Residual haemodynamic lesions and complications in repaired ASDs

• Residual shunt
• Residual RV dilatation and/or dysfunction
• Residual elevated pulmonary artery pressure
• Pulmonary venous obstruction
• Septal occluder erode to aortic root or atrial wall
• Thrombus (in region of device)
• Tricuspid regurgitation

Imaging protocol for atrial septal defect

Subcostal views	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapse to estimate RA pressure Hepatic venous Doppler to assess for venous flow pattern or flow reversal In 4 chamber view, sweep through from posterior to anterior aspect of the interatrial septum checking for defects. Add reduced colour Doppler scale and repeat. In short axis view, sweep from patient’s right to left (IAS to apex). Add reduced colour Doppler scale and repeat. Bicaval view: modified short axis view demonstrating IVC & SVC inflow. Add reduce colour scale and repeat. Rim dimensions. Maximum diameter ASD in multiple planes RV size(compared to LV size) and function Check pulmonary venous anatomy, especially for anomalous connection into SVC near RA junction.
Parasternal views	Overall RV function including the anterior wall & outflow tract Ventricular septal motion for RV volume & pressure overload Pulmonary valve anatomy & function, degree of PR Doppler of pulmonary valve & estimation of PA mean & end-diastolic pressure Anatomy of main pulmonary artery and proximal branches Aortic rim dimension Pulmonary venous return Tricuspid regurgitation. CW for RV systolic pressure Dilatation of coronary sinus
Apical views	Detailed LV function assessment. Assess aortic valve function Detailed RV size and function assessment (qualitative compared to LV size & quantitative). RA size Anterior angulation to assess anatomy and function of right ventricular outflow Assess tricuspid valve function Pulmonary venous return Posterior angulation to coronary sinus
Suprasternal views	Assessment of pulmonary venous return where possible (crab view) Assessment of branch pulmonary arteries Assessment of right +/- left-sided SVC in the setting of dilated coronary sinus

ASD Reporting:

Key points to include in transthoracic echo report:

• ASD
  • Location
  • Measurement
  • Direction of shunting
• RV size/degree of dilatation and systolic function
• RVSP or mean PA pressure
• Presence of functional TR
• Associated lesions specific to type of ASD
• LV diastolic function
• For secundum ASD and suitability of percutaneous closure:
  • Atrial septal rims are important. Comment on presence of absence of posterior rim if possible.
  • Normal pulmonary venous drainage is also important
• Post repair:
  • RV size & function as a function of remodelling
  • Patch/occluder integrity and any residual leak
  • Mitral & tricuspid regurgitation
  • RVSP
  • LV diastolic function.

Key views specific to ASD patients:

Figure 1 Subcostal long (A) and short (B) axis view of a secundum ASD (shown as *)

Figure 2 Subcostal long and short axis view of a secundum ASD taken with bi-plane imaging.

Figure3 If subcostal imaging is of poor quality, a parasternal fore-shortened view (A) or a low or high right parasternal view (B) are two good options for ASD (*) visualization

Figure 4: SVC type sinus venosus ASD seen in apical 5 chamber view (left) & zoomed views (right) (arrow)

Figure 5: SVC type sinus venosus ASD seen in zoomed subcostal view with slight clockwise rotation (left) SVASD denoted by asterisk & (right) asterisked arrow demonstrates left to right flow. Plain arrow shows normal SVC flow.

A B

Figure 6 Visualization of the 4 pulmonary veins:

From the apical 4 chamber:

A; right upper pulmonary vein

B; right lower pulmonary vein

C; left upper pulmonary vein

D;The left lower pulmonary vein is best visualized from the parasternal short axis view

C D

Figure 7

Suprasternal scan showing all four pulmonary veins entering the left atrium.

Supplementary ACHD Echo Acquisition Protocol for

Ventricular Septal Defects

The following protocol for echo in adult patients with Ventricular Septal Defects is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to unrepaired and repaired VSDs.

Background

• VSDs represent the most common congenital cardiac malformation (approx. 30% of congenital heart defects).

Diagram: Anatomic location of ventricular septal defects (VSD), viewed from the right ventricle.

1 – Doubly committed VSD;

2 – perimembranous VSD

3 – inlet VSD

4 – muscular central VSD

5 – muscular apical VSD

6 – muscular marginal VSD.

SCV – Superior vena cava; ICV – inferior vena cava; AO – aorta; PA – pulmonary artery

Diagram from Popelova et al.

• Depending on the location of the defect within the ventricular septum and the relationship to the membranous septum, perimembranous defects, doubly committed defects (also called supracristal or subarterial outlet VSDs) and muscular defects are distinguished.
  • Perimembranous defects border the membranous septum and represent the most common form (approx. 80%). These VSDs are subaortic and subtricuspid and are characterized by fibrous continuity between the aortic and the tricuspid valve. However, the defect can extend into the inlet or outlet part of the ventricular septum.
  • Muscular VSDs account for approx. 15-20% of VSDs in adults and are completely surrounded by ventricular musculature. They can occur within the inlet, apical (trabecular) or outlet portion of the RV. They may be multiple.
  • Doubly committed or outlet VSDs are characterized by a defect in the fibrous continuity between the aortic and pulmonary valves and are located directly beneath the semilunar valves. Doubly committed VSDs are typically associated with aortic cusp prolapse (usually the right coronary cusp) and AR.
  • Inlet or AVSDs: see AVSD echo protocol.
  • Gerbode defects: deficiency of the atrioventricular membraneous septum and represents a shunt from the left ventricle to the right atrium. These defects can be native or can occur post AVSD repair.
• Disruption of normal aortic valve function, namely regurgitation due to prolapsing of the right or non-coronary cusp is a recognised complication of doubly committed VSDs and also (but less commonly) in perimembranous outlet VSDs.
• A double chambered RV may develop or progress during adult life; especially in perimembranous VSDs. Particular attention is required to not overlook this lesion.
• In cases where VSDs become haemodynamically significant, it is left atrium and left ventricle which are affected by volume overload, in contrast to the right heart overload seen in atrial septal defects.

Common associations

• Left atrial and ventricular volume overload
• Elevated pulmonary artery pressure, or Eisenmenger’s physiology
• Aortic sinus prolapse and aortic valve regurgitation
• Double-chambered right ventricle

 

Surgical or trans-catheter approaches

• Surgical patch
• Percutaneous occluder

Residual haemodynamic lesions and complications in repaired VSD

• Residual shunt
• Persistent LV dilatation and systolic or diastolic dysfunction
• Residual elevated pulmonary artery pressure
• Residual aortic valve abnormalities and regurgitation
• Double-chambered RV
• Device location and interference with surrounding structures

VSD Haemodynamics

The peak pressure gradient across the VSD is obtained with CW Doppler and is useful in estimating PA systolic pressure (in the absence of RV outflow obstruction) when compared with the patient’s systolic blood pressure. In the absence of LV outflow obstruction, the systolic blood pressure is used as a surrogate for left ventricular systolic pressure. It is important to exclude pulmonary hypertension which can have a significant impact on treatment. This method of estimating RV pressure is particularly useful in cases where the VSD jet is directed towards the tricuspid valve and so contaminates the TR Doppler signal.

RVSP = BP_systolic – peak VSD gradient

A restrictive VSD describes the haemodynamic situation of the defect rather than referring to the anatomy. The term is used when a high pressure difference between left & right ventricles is maintained suggesting that RV pressure is normal and so the amount of blood passing through the defect is small.

In adults with increased LV diastolic pressure, left to right shunt may also occur during diastole which can contribute to further left heart volume overloading

Imaging protocol for ventricular septal defect

Subcostal views	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapse to estimate RA pressure Hepatic venous Doppler to assess venous flow pattern and flow reversal Identification of VSD location and size (perimembranous, muscular, doubly committed) Examine for multiple defects Retrograde flow in abdominal aorta (in cases where significant AR present)
Parasternal views	Identification of VSD location: 2D & colour Doppler sweeps of entire septum PLAX (perimembranous inlet/outlet, muscular) PSAX at level of great vessels 9-12 o’clock perimembranous VSD 12-3 o’clock outlet VSD PSAX all levels (muscular VSDs may require atypical views) 2D measurement of defect Peak CW Doppler gradient of VSD flow to assess RV pressure Assessment of Aortic valve cusp prolapse Colour Doppler assessment for AR Pulmonary valve anatomy & function, degree of PR Doppler of pulmonary valve & estimation of PA mean & end-diastolic pressure Anatomy of RVOT and main pulmonary artery and proximal branches Doppler of RVOT for double-chambered RV (interference of VSD jet may complicate interpretation) Assessment tricuspid valve (aneurysmal transformation of VSD, pseudo aneurysm) Tricuspid regurgitation. CW for RV systolic pressure (if increased TR velocity, then need to exclude double-chambered RV) LV size
Apical views	Identification of VSD location and size: apical 4 & 5 chamber views (perimembranous, inlet/outlet, muscular) Left atrial size Detailed LV function assessment. Assessment of aortic valve function RV size and function Assessment of tricuspid valve function and regurgitation (be aware that VSD jets can sometimes be confused with the TR jet depending on VSD jet direction).
Suprasternal views	Retrograde diastolic flow in descending aorta in the presence of AR.

VSD Reporting

Key points to include in transthoracic echo report:

• VSD
  • Location
  • Measurement
  • Direction of shunting
  • Systolic pressure gradient
  • Presence of diastolic flow >1m/sec suggests diastolic disease
• LV size/degree of dilatation and systolic function
• LA size
• RVSP or mean PA pressure
• Associated lesions specific to type of VSD
• For perimembraneous VSD, aortic valve function
• If associated with a double chambered RV, then gradient within the RV.

Post repair:

• LV size & function as a function of remodelling
• VSD patch/occluder integrity and residual leaks
• Presence of aortic valve regurgitation

Key views specific to VSD patients:

Fig. 1

1. parasternal long axis view of a subarterial VSD. Note that the right aorta sinus is already showing signs of prolapse. The flow through VSD shows clearly that the defect is subaortic.
2. Parasternal short axis view systolic frame: showing the high jet velocity crossing the VSD and the laminar flow in the RVOT
3. Parasternal short axis view diastolic frame: Absent septal tissue between aortic valve and pulmonary valve is characteristic of doubly committed sub-arterial VSD. The jet through VSD is very close to the pulmonary valve. Confirming that it is a subarterial VSD.

Fig. 2

Parasternal long axis view (zoom mode) showing a perimembranous VSD with:

1. aneurysmal formation (pseudo aneurysm), tricuspid valve tissue spontaneously closing the defect.
2. high velocity colour flow Doppler through the defect

Fig 3

Prolapse of the right coronary sinus (*) through a subarterial VSD sealing the VSD completely.

Fig. 4

Apical four chamber view

1. Mid-muscular VSD (*)
2. High velocity colour flow Doppler through the defect. The direction of this jet can cause problems for the correct interpretation of the CW Doppler from the tricuspid regurgitation.

Fig 5

Focused apical RV view

1. Multiple mid muscular VSDs (*)
2. Colour flow Doppler confirming the defects and showing moderate tricuspid regurgitation.

A B C

Fig 6. With the use of iRotate this unorthodox view can be acquired

1. Gives the landmarks with an asterisk marking a subvalvular narrowing. This results from the jet lesion of a small VSD and form DCRV.
2. Early systole the residual VSD jet is seen entering the RV-RVOT
3. Late systole high velocity jet from the DCRV obstruction is shown. The severity of the obstruction can also be calculated using the Vmax from the tricuspid regurgitation jet velocity.

Supplementary ACHD Echo Acquisition Protocol for

Atrioventricular Septal Defect

The following protocol for echo in adult patients with AVSD is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to repaired AVSD.

Background

• AVSDs are characterized by a common atrioventricular junction with deficient atrioventricular septation.
• This congenital heart defect is particularly common in patients with Down syndrome (prevalence of AVSD around 30%).
• Anatomic characteristics are
  • a common ovoid shaped atrioventricular junction,
  • a defect of the membranous atrioventricular septum,
  • a 5 leaflet common valve (left and right mural leaflet, right antero-superior leaflet, superior and inferior bridging leaflet),
  • an un-wedged aorta with an elongated LVOT (i.e. “gooseneck deformity”).

Diagram: Atrioventricular septal defect (AVSD):

1. normal relation between interatrial septum (IAS), atrioventricular septum (AVS), interventricular septum (IVS), and septal cusps of tricuspid (T) and mitral (M) valves;
2. incomplete AVSD (atrial septal defect type

primum)

1. complete AVSD (complete atrioventricular septal defect).

Diagram adapted from Popelova et al.

• Functionally, AVSDs can be partial with shunting only at the atrial level (also called primum ASD or partial AVSDs) or complete with shunting at atrial and ventricular level (CAVSDs).
  • Partial AVSDs present with fused superior and inferior-bridging leaflets and attachment of these bridging leaflets to the scooped out crest of the ventricular septum. These patients, therefore, have 2 valve orifices with trileaflet left AV valve (albeit with a common AV junction). As the AV valves are not morphologically true mitral and tricuspid valves, they are referred to as left and right AV valves.
  • There is a continuum between partial and complete forms. There may be a VSD that is completely or partially covered by valve tissue forming an aneurysmal basal inlet ventricular septum with or without a restrictive VSD. This is called intermediate AVSD and may – as partial AVSD – be encountered unrepaired in adults.
  • Complete AVSDs present in adult life either after repair or – if unrepaired – with Eisenmenger physiology.
• After repair, atrioventricular valve malfunction (frequently regurgitation, less commonly stenosis) requires particular attention. Morphology and malfunction mechanism require detailed analysis. Residual ASD and/or VSD, LVOT obstruction, LV and RV abnormalities, and PAP elevation must be excluded or identified.

Common associations

• See ASD protocol
• AV-valve abnormalities and LVOT obstruction
• Double orifice left AV valve
• Anomalous papillary muscles
• Parachute left AV valve
• Left ventricular volume overload
• Pulmonary arterial hypertension or Eisenmenger syndrome
• Displacement of the AV node with associated arrhythmias

Residual haemodynamic lesions and complications in repaired AVSD

• Residual shunt (atrial and ventricular level)
• RV and LV dilatation and dysfunction
• Residual elevated pulmonary artery pressure
• Left-sided AV valve regurgitation, often through the closure line between superior and inferior bridging leaflet.
• Right-sided AV valve regurgitation
• LVOT obstruction

Imaging protocol for atrioventricular septal defect

Subcostal views	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapse to assess RA pressure Hepatic venous Doppler to assess venous flow pattern and systolic flow reversal from significant right AV valve regurgitation Residual shunt (VSD, ASD, LV-RA, RV-LA shunt) maybe multiple RV size and function Retrograde flow in abdominal aorta (in cases where > moderate AR present)
Parasternal views	Shunt or residual shunt (VSD,ASD,LV-RA, RV-LA shunt) maybe multiple Left AV valve evaluation ( thickening, trileaflet, abnormal chordae) Severity and mechanism of left AV valve regurgitation (multiple jets possible) Assessment of papillary muscles (number, proximity to each other) Assess for double orifice left AV valve. Right AV valve evaluation (morphology) Severity and mechanism of right AV valve regurgitation CW Doppler flow velocity. LVOT obstruction morphology (accessory chordae, leaflet insertion, ridge) Colour Doppler (identify area of obstruction) Aortic valve morphology and quantify aortic regurgitation Doppler of pulmonary valve; degree of PR & estimation of PA mean & end-diastolic pressure Tricuspid regurgitation. CW Doppler for RV systolic pressure LV and LA dimension
Apical views	Detailed LV function assessment. Shunt or residual shunt (VSD,ASD,LV-RA, RV-LA shunt) maybe multiple Aortic valve morphology and quantify aortic regurgitation LVOT obstruction (PW at multiple levels to identify the level of obstruction) Left AV valve evaluation ( thickening, septal commissure, abnormal chordae) Severity and mechanism of left AV valve regurgitation (multiple jets possible) CW for left AV valve gradient (especially after repair) Right AV valve evaluation (morphology) Severity and mechanism of right AV valve regurgitation Detailed RV size and function assessment (qualitative compared to LV size & quantitative). LA and RA size
Suprasternal views	Assessment aortic valve Doppler gradient and regurgitation

AVSD Report Template

Key points to include in transthoracic echo report:

• Complete, partial or transitional AVSD
• Size of atrial and ventricular components
• Direction of shunting for both components
• AV valve chordal anatomy (if considered for surgery, especially straddling)
• AV valve regurgitation
• Estimate of pulmonary pressure
• Other associated lesions
• Ventricular size & function

Post repair

• Residual ASD or VSD
• Residual LV-RA shunting (Gerbode like defects)
• Left & right AV valve function
• Left & right ventricular size & function
• Estimate of pulmonary pressure
• Evaluation of associated lesions e.g. LV outflow obstruction

Key views specific to AVSD patients:

Fig 1. A: Parasternal long axis RV inflow view shows the atrial septal defect (asterisk) with Clear visualization of AV valves, on the same level. B. Parasternal short axis view showing the three leaflets (asterisk) of the left AV valve. Arrow indicates the commissure between anterior and posterior bridging leaflets

Fig 2. A: Apical 4c view AV valves are on the same level. Arrow shows the small atrial septal defect. LV and LA are dilated due to sever left AV regurgitation. B. Zoom of the AV junction showing clear chordae attachments of the superior bridging leaflet on to the septum (asterisk) . No ventricular shunt was present. Arrow shows the small atrial septal defect.

Figure 3: complete AVSD apical view in diastole

Figure 4 Partial AVSD/primum ASD. (Left) shows the primum ASD in diastole. (Right) shows no offset of the individual AV valves

Figure 5: (left ) trileaflet left AV valve & (right) regurgitation arising from the anterior closure line /line of apposition. This is seen in partial AVSD and also in repaired common AVSD.

Supplementary ACHD Echo Acquisition Protocol for

LV outflow obstructions

The following protocol for echo in adult patients with LV outflow obstructions, including subvalvular, valvular, supravalvular stenoses and coarctation and is intended as a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to LV outflow evaluation.

Background:

This document incorporates the following lesions:

• Subvalvular aortic stenosis, including subaortic membranes
• Valvular stenosis, including bicuspid & dysplastic aortic valves
• Supravalvular stenosis, including hourglass narrowings and hypoplastic ascending aorta
• Coarctation of the aorta

Diagram: Aortic coarctation: relationship to the origin of the left subclavian artery is important to identify. Diagram adapted from Popelova et al

Common associations:

• Subaortic membrane
  • bicuspid aortic valve, coarctation, supramitral ring, parachute mitral valve (when all features are present, this condition is collectively referred to as Shone syndrome)
  • aortic regurgitation
• Bicuspid aortic valve – ascending aorta dilatation, coarctation, Turner syndrome
• Supravalvular stenosis – Williams syndrome
• Coarctation – bicuspid aortic valve

Common sequelae:

• Aortic regurgitation
• LV hypertrophy
• LV systolic & diastolic dysfunction
• In severe cases, pulmonary hypertension, secondary to LV diastolic dysfunction.
• Clinically in coarctation, reduced femoral pulses or arm-leg blood pressure gradient

Tips & Tricks:

1. Subaortic stenosis:

• Assess for cause of obstruction: e.g. subaortic membrane/ridge/chordae crossing outflow tract, diffused tunnel like narrowing or basal septal hypertrophy
• Turbulent flow through LVOT can damage aortic valve leaflets and cause aortic regurgitation
• Assess timing of flow – often a dynamic obstruction peaks in late systole whereas a fixed obstruction peaks in mid systole. This has important implications for patient management.

1. Aortic valve stenosis:

• Assess valve anatomy and number of leaflets
• Assess for co-existing aortic regurgitation, often eccentric if bicuspid aortic valve
• Assess aortic root and ascending aorta for dilatation (using higher left parasternal & right parasternal views)
• Use apical, suprasternal and right parasternal windows as minimum attempt to search for best Doppler/blood flow alignment to reflect the true gradient. Bicuspid valve flow is often eccentric. Non-imaging probe is highly recommended.
• Use modified Bernoulli equation to correct gradients if LVOT velocity >1.2m/sec (see below).

1. Supravalvular aortic stenosis:

• Identify level of stenosis e.g. sinotubular junction or in ascending aorta (right parasternal or apical long axis views may be helpful).
• Identify extent of stenosis – discrete or long, tunnel like narrowing (important Doppler considerations-see below)
• Use multiple windows to identify true gradient
• Confirm that aortic valve function is normal.

1. Coarctation:

• Unexplained concentric left ventricular hypertrophy can be the important clue to coarctation.
• Assess descending aorta with CW Doppler, including the non-imaging probe.
• The shape of the CW Doppler signal is more informative than the peak velocity: extension of forward flow into diastole can suggest the presence of severe stenosis and a collateral circulation, which is clinically significant, irrespective of peak gradient. In a normal situation, the cessation of aortic flow will coincide with the end of the T-wave on the ECG. In coarctation, forward flow is seen after the T-wave. This flow is often referred to as a ‘diastolic tail’.
• In long segments of coarctation, the CW Doppler gradient can be unreliable due to the assumptions of the Bernoulli equation being untrue and also the presence of significant collaterals providing an alternative pathway for flow.
• In the suprasternal view, be careful not to confuse ‘double shadows’ given by flow in the left pulmonary artery, which courses in front of the descending aorta
• Assess abdominal aortic flow for systolic blunting and any diastolic continuation of flow
• In the case of extensive collateralization, mild exercise (supine pedalling motion increasing the heart rate to 90-100 bpm) may saturate the collaterals, force flow through the coarctation and reveal the gradient.

Imaging Protocol for LV outflow obstruction

PLAX/RV inflow	LV size & function LV wall thickness Demonstrate LV outflow tract, aortic valve anatomy, number of leaflets, aortic root and ascending aorta Assess valvular function Assess site of stenosis
Apical views	Obtain LVOT VTI with PW Doppler Obtain peak outflow gradients and VTI using CW Doppler (with non-imaging probe) Assess AoV regurgitation Assess level of stenosis Assess ventricular function Assess diastolic function Assess TR for pulmonary hypertension
Subcostal view	Assess abdominal aortic flow profile
Suprasternal views	Assess arch dimensions, site of narrowing, peak gradient, presence of diastolic forward flow. Attempt to demonstrate collaterals if coarctation; may use mild exercise (see tips and tricks) Obtain peak aortic/outflow gradient & VTI from suprasternal notch & clavicular views. Use of non-imaging probe is recommended
Right parasternal	Assess dimensions & contour of ascending aorta Assess peak aortic gradient. Use of non-imaging probe is recommended

Technical considerations:

1. The Simplified Bernoulli equation.

• The simplified Bernoulli equation is used frequently throughout echocardiography and converts a velocity to a pressure gradient using the equation:

ΔP = 4V²

• It is simplified from a much more complex equation which accounts for convective acceleration, flow acceleration and viscous friction. The simplified equation holds multiple assumptions.
• One of the assumptions is that there is no substantial acceleration of proximal flow which is valid when proximal flow is <1.2m/sec.
• In instances when proximal flow is ≥1.2m/sec, the modified Bernoulli equation must be used in order to prevent over-estimation of gradients:

ΔP = 4 (V₂² – V₁²)

where V₂ = peak obstructive gradient (CW Doppler)

& V₁ = velocity proximal to obstruction (PW Doppler)

Case example:

LVOT Vmax 1.6m/sec AoV Vmax 3.1m/s

LVOT peak gradient 10mmHg AoV peak gradient 38mmHg

LVOT mean gradient 7mmHg AoV mean gradient 22mmHg.

In this dataset, the LVOT flow is elevated at 1.6m/sec and is outside the defined ‘negligible’ contribution to the peak aortic velocity as stated in the Bernoulli equation. Therefore, these aortic gradients should be corrected.

Corrected peak AoV gradient = 4 (V₂² – V₁²)

= 4 (3.1² – 1.6²)

= 4 (9.61-2.56)

= 4 * 7.05

= 28mmHg.

Corrected mean gradient = AoV mean gradient – LVOT mean gradient

= 22 – 7

= 15mmHg.

In practical terms, this scenario most commonly arises in both aortic stenosis and in coarctation when the LVOT flow or PW Doppler just proximal to the coarctation has a velocity >1.5m/sec.

1. Long tubular narrowings:

• The Bernoulli equation is valid for discrete, localised obstructions. Where there are long tubular narrowings e.g. hypoplastic ascending aorta or long segments of coarctation, the Bernoulli equation does not accurately reflect the true pressure gradient due to rapid pressure recovery. Echo-derived gradients can appear over-estimated when compared to invasively-derived catheter gradients.

1. Multiple sites of narrowing

• Special caution should be taken in the setting of multiple sites of stenosis e.g. severe AS with coarctation as multiple assumptions of the Bernoulli equation can be violated simultaneously and therefore Doppler gradients become increasingly unreliable. Peak velocity and timing of flow may provide an idea of the gradient but alternative imaging modalities are recommended.

Bicuspid Aortic Valve Reports

Key points to include in transthoracic echo report:

• LV size, function & wall thickness
• Valve anatomy: true bicuspid versus functionally bicuspid, if so name the fused cusps
• Valve function: peak & mean gradients, AVA, indexed stroke volume
• Aortic measurements: LVOT, hingepoint, trans-sinus, sinotubular junction, ascending aorta, arch & isthmus
• Presence of coarctation
• Estimate of pulmonary pressure
• Assess for other associated anomalies

Key Views Specific to LV outflow tract obstructions:

1. Parasternal long and short axis views with aortic root/ascending aorta and view of bicuspid aortic valve.
2. M-mode recording of aortic valve movement in patient with sub-aortic stenosis.
3. Apical 5 chamber showing sub aortic stenosis CFI
4. Apical 5 chamber CW Doppler showing AS signals
5. Suprasternal view with diastolic tail versus normal
6. Abdominal aorta PW Doppler – 1 normal showing early diastolic flow reversal then diastolic forward flow as normal and 2^nd showing a true diastolic tail

Parasternal long axis with subaortic membrane 2D & CFI

A

B

C

D

Figure 1: Subaortic membrane: A) subaortic membrane seen clearly in the outflow tract. LVH. B) turbulent colour flow arising from LVOT. C) apical long axis view showing membrane and LVOT turbulence D) CW Doppler confirms severe outflow tract obstruction

Figure 2. M-mode recording of aortic valve showing mid systolic closure of the aortic valve (arrow) in patient with sub aortic stenosis

Figure 3: Tunnel like sub-aortic stenosis. A) Parasternal view showing diffused narrowing of LVOT with turbulent flow on colour Doppler. B) Apical five chamber view showing hypertrophied muscular tissue causing narrowing LVOT. C) CW Doppler confirms severe outflow tract obstruction

Figure 4. Bicuspid aortic valve. a)Parasternal long axis view showing bicuspid aortic valve and measurement of aortic root dimensions at ventriculo-arterial junction, trans-sinus, ST junction and ascending aorta. b) Parasternal short axis view demonstrating a bicuspid aortic valve during ventricular systole with limited opening orifice.

A

B

C

Figure 5. Coarctation of aorta. A) Supra-sternal view of aortic arch, narrowing at proximal descending aorta (arrow). B) Colour Doppler Mapping showing turbulent flow across the site of coarctation. C) continuous wave Doppler recording in the descending aorta showing increased peak systolic flow velocity with long diastolic tail (arrow) characteristic for significant coarctation of aorta.

A

B

C

Supplementary ACHD Echo Acquisition Protocol for

Ebsteins Anomaly

The following protocol for echo in adult patients with Ebsteins anomaly is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to Ebstein’s patients.

Definition:

• Apical displacement of the septal leaflet of the tricuspid valve into the right ventricle. The posterior leaflet is sometimes also displaced. The leaflets have failed to fully delaminate from the septum and are often dysplastic with thickened, rolled & shortened chordae and under-developed papillary muscles
• Anterior leaflet is elongated and redundant with abnormal chordal attachments directly to the lateral wall.
• “Atrialization” of the basal portion of the right ventricle (aRV) with abnormal ventricular septal motion.

Septal leaflet

Annulus

Posterior leaflet

Anterior leaflet

Coronary sinus ostium

Patent foramen ovale

Fenestrations

Diagram 1 Diagram of Ebstein anomaly. Adapted from Ebstein W. Ueber einen sehr seltenen Fall von Insufficienz der Valvula tricuspidalis, bedingt durch eine angeborene hochgradige Missbildung derselben. Arch Anat Physiol. 1866; 238–255.

Common associations:

• ASD or PFO (bi-directional shunting is common)
• VSD
• Pulmonary atresia with intact ventricular septum
• MV prolapse
• Coarctation of aorta
• LV non compaction

Carpentier’s Classification in Ebstein Anomaly

D.

C.

B.

A.

Diagram 2 Carpentier’s Classification. Type A: the volume of the true right ventricle (RV) is adequate; Type B: a large atrialized component of the RV exists, but anterior leaflet of the tricuspid valve moves freely; Type C, the anterior leaflet is severely restricted in its movement and may cause significant obstruction of the right ventricular outflow tract; Type D, almost complete atrialization of the RV except for a small infundibular component. (Carpentier A, et al. A new reconstructive operation for Ebstein’s anomaly of the tricuspid valve. J Thorac Cardiovasc Surg. 1988;96: 92–101. )

Diagram 3. Different types of Ebstein anomaly. Diagram adapted from Popelova et al.

Celermajer Index in Ebsteins Anomaly

The Celermajer Index (CI) compares the combined right atrial and atrialised right ventricular area to the area of the remainder of the cardiac chambers seen in the apical 4 chamber view and correlates with prognosis in neonates.

Figure 1: Celemajer Index measurements

Celermajer Index = Total area of right atrium + atrialised RV

Total area of functional RV + LA + LV

Celermajer’s echocardiographic grading score: the ratio of the combined area of the right atrium and atrialized right ventricle is compared with that of the functional right ventricle and left heart:

grade 1: ratio <0.5;

grade 2: ratio 0.5 to 0.99;

grade 3: ratio 1.0 to 1.49,

grade 4: ratio >=1.5

A ratio ≥1 in a neonate indicates a very poor prognosis.

(Celermajer DS, et al. Ebstein’s anomaly: presentation and outcome from fetus to adult. J Am Coll Cardiol. 1994;23:170 –176.)

Imaging protocol for Ebstein anomaly

Subcostal views	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapsing Assess atrial septum RV SAX may offer biplane FAC of RV
PLAX/RV inflow	Assess displacement of septal +/- posterior leaflet involvement Assess TR severity Measure LV size TV leaflets seen in RVOT in standard PLAX suggest anterior rotation of the tricuspid orifice
Parasternal short axis	Assess rotation of tricuspid valve closer in position to the pulmonary valve Assess TR severity Assess RVOT dilatation & function Assess size of pulmonary arteries when repair is being considered Assess interatrial septum
Apical views	Zoom on cardiac crux to establish & measure abnormal septal displacement (>2 cm or >8mm/m²) Assess tricuspid valve anatomy including degree of direct attachment of anterior leaflet into lateral wall of RV Assess functional right ventricular function Assess degree of atrialisation of right ventricle (Celemajer Index) Assess TR severity at origin of jet (large compliant RA may mask hepatic flow reversal) Assess left ventricular function
Suprasternal views	Assess aortic arch SVC flow may show flow reversal in cases of severe TR.

Ebstein Anomaly Reports:

Key points to include in transthoracic echo report:

• Valve anatomy including displacement towards apex and rotation towards the RV outflow tract
• Functional RV size & function. In severe cases, this may be only the RVOT
• Degree of atrialisation of the right ventricle
• Severity of tricuspid regurgitation
• Size of pulmonary arteries
• LV size & systolic function
• Atrial septal integrity

Key views specific to Ebsteins Anomaly:

Figure 3. Apical 4 chamber view demonstrating significant apical displacement of the TV septal leaflet (arrow). A large component of the RV is atrialised. .

Fig ure 2. PLAX: note the abnormal enface orientation of the tricuspid valve. This demonstrates the abnormal anterior rotation of the valve. The RV is also dilated.

Figure 4. Severe TR from 4 chamber view with tricuspid valve Doppler profile. Note the laminar flow of tricuspid regurgitation indicating severe deficiency of valve function. Estimation of pulmonary pressures is not reliable in this scenario.

A B

S

P

A

AoV

B

Figure 5. Carpentier type IV Ebsteins: in the 4 chamber view (A), there are no discernible leaflets due to marked anterior rotation of the valve, only the moderator band is seen. In the 5 chamber view (B), with the aortic valve as a landmark, all 3 leaflets are seen enface.

Supplementary ACHD Echo Acquisition Protocol for

Repaired Tetralogy of Fallot

The following protocol for echo in adult patients with repaired Tetralogy of Fallot (TOF) is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to repaired TOF.

Background

TOF is the most common cyanotic congenital heart disease. Anatomic malformations include:

1. RVOT obstruction, typically subpulmonary infundibular stenosis

2. VSD

3. Overriding aorta

4. RV hypertrophy

Diagram of tetralogy of Fallot. Diagram adapted from Popelova et al

Infundibular stenosis

Aorta overriding the VSD

Common associations

• ASD (~33% of cases) (Tetralogy anatomy + ASD = Pentalogy of Fallot)
• Right aortic arch (25%)
• Coronary artery anomalies (up to 10%). The commonest is when the LAD arises from the RCA & crosses RVOT anteriorly which has important implications for the surgical approach.
• Aortopulmonary or bronchopulmonary collaterals
• 22q11 deletion (15%)
• Persistent left SVC (10%)
• AVSD (2%)

Surgical approaches

Strategies and timing of surgical repair have evolved over time. Currently systemic to pulmonary shunts are no longer performed except in rare cases and total repair is done in the first 3-6 months of life.

• RVOT patch + VSD closure – in setting of adequate pulmonary annulus. Procedure of choice
• Transannular RVOT patch + VSD closure – to increase RVOT/pulmonary annulus size
• RV-PA conduit + VSD closure – most often used in the setting of coronary artery anomalies +/- augmentation of pulmonary arteries.
• BT shunt (classic or modified) is a palliative procedure to encourage growth of pulmonary arteries in neonates. Historically, in rare cases, Waterston shunt (ascending aorta to right pulmonary artery) and Potts shunt (descending aorta to left pulmonary artery) were performed.

Residual anatomic and haemodynamic lesions in repaired TOF

• Residual pulmonary regurgitation
• Residual or recurrent RVOT obstruction and branch PA stenosis
• Akinetic RVOT free wall and RV dilatation and dysfunction
• Restrictive RV
• Residual VSD, ASD
• Tricuspid regurgitation
• Aortic dilatation and regurgitation
• Left ventricular dysfunction
• Conduction and rhythm abnormalities

Imaging protocol for repaired Tetralogy of Fallot

Subcostal views	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapse to assess RA pressure Hepatic venous Doppler to assess for increased A wave reversal velocity Ventricular septum for residual VSDs Anterior angulation to assess anatomy and function of right ventricular outflow RV wall thickness and RV function
Parasternal views	Overall RV function including specifically the anterior wall & outflow tract RVOT anatomy – aneurysmal, narrowing Pulmonary valve annulus diameter, function, degree of PR Doppler of pulmonary valve for gradients & estimation of pulmonary pressures, including presence of forward ‘a’ wave indicating restrictive RV physiology Identify level of stenosis where relevant Anatomy of main pulmonary artery and proximal branches, including branch dimensions. Ventricular septal motion for signs of volume or pressure overload Aortic annulus, root and ascending aorta diameters, degree of AR Integrity of VSD patch Dilatation of coronary sinus
Apical views	Detailed LV function assessment. Assess aortic valve function Detailed RV size and function assessment including fractional area change. Anterior angulation to assess anatomy and function of right ventricular outflow Assess tricuspid valve function Posterior angulation to coronary sinus
Suprasternal views	Assessment of arch sided-ness by demonstrating innominate artery bifurcation. Assessment of branch pulmonary arteries and PR Assessment of right +/- left-sided SVC in the setting of dilated coronary sinus Wide sweeps to assess for aortopulmonary or bronchopulmonary collaterals

Repaired Tetralogy of Fallot Reports

Key points to include in transthoracic echo report:

• RV size, systolic and diastolic function
• Pulmonary valve function
• VSD patch integrity
• Aortic root dilatation
• Estimate of pulmonary pressure
• Assess for PA branch stenosis

Key views specific to ToF repair patients:

Parasternal long axis view

Figure 1 The arrow points to the VSD patch which is brighter than the myocardium. Note that the aortic root still slightly overrides the ventricular septum. The right ventricle is dilated as is commonly seen in adults with repaired ToF, usually associated with pulmonary regurgitation.

Parasternal short axis views

Figure 3 PA bifurcation: Diastolic flow reversal is noted in the pulmonary branches indicating severe PR, a common finding in repaired ToF. The trans-annular patch interrupts the integrity of the pulmonary annulus.

Figure 2 The RVOT is dilated and usually has some akinetic regions following repair using the trans-annular patch technique. The aortic root appears irregular due to the VSD patch. Careful interrogation with CFI is warranted to exclude residual VSDs.

Figure 4 CW Doppler profile of the pulmonary valve: Note the PR ends prematurely in mid diastole due to rapid equalisation of RV & PA pressures. This can indicate severe PR (combined with a wide colour jet).

PW RVOT Doppler

Figure 5. PW Doppler, with Doppler sample at the tip of the pulmonary valve, demonstrates forward flow following atrial systole or a forward ‘a wave’. This suggests RVEDP is markedly elevated, higher than PAEDP which opens the pulmonary valve during atrial systole. It can vary throughout the respiratory cycle. RV restrictive physiology is suggested when the forward a wave is present for 5 consecutive beats during normal respiration. This is often complemented by high velocity atrial reversals in the hepatic veins.

Supplementary ACHD Echo Acquisition Protocol for

TGA – Atrial Switch repair (Mustard/Senning)

The following protocol for echo in adult patients with Transposition of the Great Arteries (TGA) and atrial switch repair is intended as a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to TGA with atrial switch repair.

Atrial Switch Surgical Techniques

Mustard & Senning operations establish appropriate connection between the systemic venous pathways and the subpulmonic ventricle and between the pulmonary venous pathway and the systemic ventricle at the expense of a morphological right ventricle support systemic circulation.

• They share a similar goal which serves to create the following flow patterns:
  • Flow from the IVC & SVC is redirected to the left atrium – left ventricle – pulmonary artery
  • Pulmonary venous flow is redirected to the right atrium –right ventricle – aorta.
• While these two operations differ surgically, the echocardiographic appearance is indistinguishable.

 

1. Mustard procedure B. Senning Procedure

Diagram A. Mustard Procedure: Uses baffles made from Dacron, GoreTex or pericardial tissue to redirect flow B. Senning Procedure: Uses tissue from the right atrium and the atrial septum to redirect flow. Diagrams from Popelova et al

Post-operative Sequelae:

Baffle obstruction

o SVC baffle obstruction more common following Mustard operation

o PV baffle obstruction is more common following Senning operation

Baffle leaks

o Small leaks are common and not haemodynamically important, except in the case of cryptogenic stroke

o Large leaks are rarer but important due to associated volume overload

LV outflow obstruction (33% patients)

o Produces pulmonary stenosis & protects pulmonary arterial bed

o Can be dynamic or fixed

Pulmonary hypertension

o is reported in up to 7% of patients, especially in those with prior VSD and those repaired later in life. Can cause LV dilatation & loss of usual sub-pulmonary LV crescent shape

Systemic RV

o Hypertrophy

o Dilatation (lack of reference values for systemic RV)

o Systolic function invariably deteriorates over time

Tricuspid regurgitation

o The tricuspid valve regurgitation is predominantly due to annular dilatation and is likely functional rather than due to primary organic abnormality. In rare cases, structural tricuspid valve abnormalities also exist.

Imaging protocol for TGA atrial switch

Subcostal view	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapsibility Hepatic venous Doppler to assess for evidence of IVC baffle stenosis Assessment of RV wall thickness & preliminary assessment of size & function Baffle assessment as sometimes well aligned for Doppler
Apical views	Atrial baffles: Pulm veins-RA best seen in ap4 IVC-LA best seen in ap4 with posterior angulation & slight anti-clockwise rotation. Also seen ap2. SVC-RA best seen in ALAX. Can also be seen in ap2. Pacing lead may provide a clue. CFI & PW Doppler looking for phasic forward flow through pathways. In normal situation, baffle velocity <1.0m/sec but phasic flow is the most important feature. CFI to assess for baffle leaks. The CF scale or Nyquist limit might need to be reduced to appreciate small shunt. Agitated saline study may be required to exclude leaks in venous baffle. Atrioventricular connection Including valvular morphological & functional assessment Systemic RV assessment: Size & function assessment for comparison with previous study. Normal reference ranges do not apply. Subpulmonary LV assessment: LV typically small & crescent-shaped with septum bowing towards the LV. A normal sized or dilated LV may indicate pulmonary hypertension or baffle leak with significant left to right shunt. Pulmonary/left ventricular outflow: Assess for obstruction Assess diastolic pressures from pulmonary regurgitation velocity
PLAX/RV inflow	Assess LV size & geometry (should be small & crescent-shaped, compressed by the systemic RV). Demonstrate parallel relationship of the great vessels with aorta anterior Assess pulmonary artery & aortic root size Assess for aortic regurgitation (contributes to systemic RV volume overload) Demonstrate SVC-LA baffle with CFI in long axis view Assess for pulmonary regurgitation
Parasternal short axis	Demonstrate anterior/posterior & left/right relationship of great vessels Assess biventricular function & septal curvature (should be toward LV, if straight/normal may suggest pulmonary hypertension) Demonstrate IVC-LA baffle with CFI Demonstrate pulmonary venous-RA baffle CFI Assess for baffle leak or VSD
Suprasternal views	Assessment of pulmonary branches SVC flow PW Doppler assessment is useful in assessing the SVC-LA baffle if obstructed or may show flow reversal in the setting of significant leak.

TGA Atrial Switch Reports

Key points to include in transthoracic echo report:

• Systemic RV size (serial comparison) and systolic function
• Systemic valve function
• Sub-pulmonary LV size (should be smaller than normal) and systolic function
• Estimate of mean PA pulmonary pressure from PR Doppler
• Baffle patency and any evidence of leaks

Key views specific to atrial switch patients:

Subcostal Views:

Figure 1 Pulmonary Venous pathway: A) The arrow shows the pulmonary venous pathway. B) Red colour flow shows pulmonary venous flow entering into the pulmonary venous atrium (PVA).

Apical 4 Chamber View:

Figure 2 Typical apical 4 chamber view in an atrial switch patient. sRV:systemic right ventricle; pLV: sub-pulmonary left ventricle; LA: morphologic left atrium; PVB: pulmonary venous baffle; PVA: pulmonary venous atrium;

Figure 3 Apical 4 chamber view showing A) pulmonary venous flow into the right atrium & B) IVC flow into the left atrium – slight posterior angulation and anti-clockwise rotation is often helpful for obtaining a longitudinal section of the IVC baffle (IVCB).

Apical 2 Chamber View:

Figure 4 IVC baffle from 2 chamber view, also showing the pulmonary venous atrium in cross-section

Apical Long Axis View:

Figure 5 SVC baffle seen entering the left atrium.

Parasternal View:

Figure 6 A)Small crescent-shaped LV (LV dimension demonstrated by arrow) & B) dilated LV suggestive of LV pressure or volume overload

Figure 7 Variation of LV size with respiration

Figure 8 Parallel relationship of great vessels.

Figure 9 PLAX view of SVC pathway with pacemaker wire (arrow) just posterior from PA

Parasternal Short Axis Views:

Figure 10 A) Anterior/posterior relationship of great vessels. The aorta is anterior and to the right of the pulmonary artery. B) Normal appearance post atrial switch: the high pressures in the systemic RV cause reversed septal curvature and push the ventricular septum towards the left.

Parasternal Short Axis Views:

Figure 11 PSAX views demonstrating A) pulmonary venous baffle, B) IVC-LA baffle

Parasternal Short Axis Views:

Figure 12 Arrows shows IVC baffle leak from PSAX view.

Figure 13 A) Normal respiratory variation noted in hepatic veins. B) Pulsed Doppler from R supraclavicular view of SVC; phasic and returning to baseline, suggesting no obstruction.

Figure 14 Flow profiles in pulmonary venous pathway. Top) Elevated flow velocity in baffle >1.0m/s but flow still returns to baseline suggests mild stenosis. Bottom) continuous flow which never returns to the baseline suggests significant stenosis. The waveform is the most important indicator of obstruction rather than velocity.

Figure 15 A positive bubble study showing a fully opacified sub-pulmonary LV and bubbles crossing into the systemic ventricle. This demonstrates pulmonary -to-systemic circulation shunting suggestive of baffle leak

Supplementary ACHD Echo Acquisition Protocol for

TGA – Arterial Switch repair

The following protocol for echo in adult patients with Transposition of the Great Arteries with arterial switch repair is intended as a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to TGA with arterial switch repair.

Arterial Switch Operation – Surgical Techniques

The arterial switch operation corrects d-transposition circulation and anatomy by connecting the great vessels to their appropriate ventricles. This has been the standard operation for dextro-transposition (d-TGA) since the mid-late 1980’s and is usually performed in the first week of life.

Diagram. Jatene’s arterial switch operation – diagram adapted from Popelová et al

• Jatene’s arterial switch operation involves transection of both great arteries above the semilunar valves and then
  • the aorta (originally arising from the right ventricle) is transferred to its correct position and is connected to the left ventricle. The valve (which was the pulmonary valve) remains in position and is now known as the neo-aortic valve – it functions as an aortic valve but is morphologically a pulmonary valve.
  • the coronary arteries & buttons are explanted from the pulmonary root are reimplanted into the neo-aortic root.
  • the main pulmonary artery is pulled from its posterior position so that it becomes anterior to the aorta (LeCompte manoeuvre). The branch arteries now straddle the aorta, unlike in the normal branch artery anatomy. Not all patients with arterial switch operation have this LeCompte procedure. Reference to the surgical notes of individual patients is recommended.
  • the original aortic valve remains untouched and is now referred to as the neo-pulmonary valve.

Post-operative Sequelae:

• Supravalvular pulmonary artery stenosis, caused by scarring at the anastomosis or origin of the branch arteries, requires re-intervention in about 5–30% of patients
• Supravalvular aortic stenosis occurs less often, with re-intervention required by about 2% of patients
• Right ventricular outflow tract obstruction (RVOTO) develops in the presence of a hypertrophic infundibulum
• Progressive dilatation of the neoaortic root occurs more often in complex TGA (with VSD) which can compress the branch pulmonary arteries
• Various degree of aortic valve regurgitation occurs in up to 50% of patients
• LV systolic dysfunction often seen in patients with coronary artery anomalies

Imaging Protocol for TGA – arterial switch repair

Subcostal view	Establish abdominal and atrial situs, cardiac position & direction of apex
Apical views	Ventricular function Global ventricular function Assessment of regional wall motion abnormalities related to stenosis of re-implanted coronary arteries Assess for myocardial perfusion with contrast Valvular assessment Aortic regurgitation Superior angulation for pulmonary regurgitation or supravalvular stenosis
PLAX views	Routinely measure aortic root assessing for dilatation and supravalvular stenosis Assess for aortic regurgitation & supravalvular narrowing Assess for pulmonary regurgitation Assess for supravalvular pulmonary stenosis including in the main, left and right pulmonary arteries
Parasternal short axis	Use a very high PSAX view to demonstrate the branch pulmonary arteries +/- LeCompte manoeuvre Careful interrogation of stenosis at all anastomosis sites along the pulmonary artery – including left & right branch PAsAssess aortic regurgitation
Suprasternal views	Careful assessment of pulmonary branches – use of alternative windows e.g. supraclavicular views may be helpful Assess for supravalvular aortic stenosis

TGA Arterial Switch Reports

Key points to include in transthoracic echo report:

• RV size & function
• Estimate of RV systolic pressure
• Patency of PA branches, especially when LeCompte performed
• LV size & systolic function
• Aortic valve function
• Aortic root size

Key views specific to arterial switch patients:

Figure 1 High PSAX view demonstrates the LeCompte manoeuvre. The pulmonary artery branches straddle the ascending aorta. This patient has dilated pulmonary arterial branches due to PA hypertension. This view can be difficult to obtain in majority of patients.

Figure 2 Another example of the LeCompte manoeuvre. Note on the 2D image the origin of the RPA is narrowed, resulting in stenosis & turbulent colour flow.

Figure 3 Supravalvular aortic stenosis at the aortic root anastomosis site. The sinotubular junction is measured here.

Figure 4 Dilatation of the neo-aortic root (original pulmonary root) may cause aortic regurgitation.

Supplementary ACHD Echo Acquisition Protocol for

Rastelli repair

The following protocol for echo in adult patients with a Rastelli procedure and is intended as a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to Rastelli repair.

Rastelli Operation – Surgical Technique:

Rastelli operations are performed most commonly in patients with a variety of congenital abnormalities, the common theme being the presence of a ventricular septal defect frequently associated with right ventricular outflow tract obstruction:

• Double outlet right ventricle with a VSD
• Transposition of the great arteries with a VSD
• Truncus arteriosus

Diagram. Rastelli operation

diagram adapted from Popelová et al

The procedure uses a patch to deviate blood from the left ventricle, across the native ventricular septal defect, to the aorta (which in VA discordance remains in its anterior position). The preoperative location of the VSD is important; VSDs which are committed to the great arteries fare better than remotely located VSDs, which are difficult to use in the re-routing of LV outflow.

Where present, the native pulmonary artery is disconnected proximally and a valved right ventricular to pulmonary artery conduit is inserted. The location of the conduit is usually very anteriorly in close proximity to the sternum, which often necessitates the use of non-standard imaging windows to profile with echocardiography.

Post-operative Sequelae:

• LV outflow obstruction
• RV-PA conduit dysfunction
• VSD patch leak
• Aortic root dilatation
• Bi-ventricular dysfunction
• Arrhythmias

Imaging Protocol

Parasternal views

Assess integrity of VSD patch Exclude LVOT gradient -often better alignment than in apical views due to acutely angulated LVOT. Use high parasternal views to assess RV-PA conduit as is an extracardiac conduit – it is usually located very anteriorly and requires non standard views. Aim to interrogate both proximal & distal ends of the conduit as it can narrow at either end. It may be useful to palpate for the thrill associated with the conduit stenosis and to place the transducer at that location. Assess for aortic root dilatation

Apical views

Note serpiginous route of LV outflow, exclude obstruction & assess aortic valve function. Assess integrity of VSD patch Ventricular function in the setting of arrhythmias Obtain RVSP using TR jet. RVSP>2/3 systemic blood pressure suggests significant RVOT obstruction or presence of pulmonary hypertension.

Rastelli Repair Report

Key points to include in transthoracic echo report:

• Clearly state the original anatomy. Rastelli operations can be used for other anatomies as well as dTGA.
• VSD patch integrity
• LV outflow haemodynamics
• Aortic root size
• RV-PA conduit haemodynamics & assess for regurgitation
• Estimate of RV systolic pressure

Key views specific to Rastelli Repair:

Parasternal views:

AoV

VSD patch

VSD

Figure 1 The aorta remains in its anterior position and the LV outflow is through the VSD. The LVOT becomes elongated and sometimes acutely angulated. It is important to identify LVOT obstruction using colour and Doppler.

VSD

Figure 2 A residual VSD patch leak. The patch re-routes the flow from the LV to the anterior aorta, and so can be quite long.

Figure 3 RV-PA conduit: this is usually positioned right underneath the sternum and requires very high parasternal views. The conduit is long and can narrow at either end, hence assessing the length of the conduit is important and may require multiple views as seen here.

Apical views:

Figure 4 The elongated LVOT has increased musculature at the VSD site which causes LV outflow obstruction.

Supplementary Echo Acquisition Protocol for

Congenitally Corrected Transposition of the Great Arteries

The following protocol for echo in adult congenital heart patients with congenitally corrected transposition of the great arteries (ccTGA) is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to ccTGA patients.

Background

Congenitally or “physiologically corrected” transposition of the great arteries is a congenital heart condition characterized by discordant atrioventricular and ventriculo-arterial connections. It is also known as double discordance, levo-TGA and cc-TGA. It is a very uncommon congenital heart defect (0.5% of congenital heart defects). The RV is the subaortic ventricle supporting the systemic circulation and the LV is the subpulmonary ventricle supporting the pulmonary circulation. The systemic AV valve is the morphologically tricuspid valve.

Diagram. ccTGA: discordant atrioventricular and ventriculo-arterial connections

Diagram from Popelova et al

Common associations

VSD

Tricuspid valve (systemic AV valve) abnormalities e.g. Ebstein-like malformation

Tricuspid regurgitation

Aortic regurgitation

Systemic right ventricular dysfunction

Subvalvular pulmonary stenosis

Malalignment of the atrial septum and inlet part of the IVS in usual arragement in the atria (reversed crux).

Heart block

Mesocardia, dextrocardia.

Imaging protocol for cc-TGA

View	Area of interest
Subcostal view	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapse to assess RA pressure Systemic RV function assessment (visual) Systemic RV wall thickness assessment Tricuspid valve morphology, mechanism and severity of TR Retrograde flow abdominal aorta (in cases where > moderate AR present)
Parasternal views	In ccTGA, initial images can be confusing. No standardized parasternal long axis views are possible Use short axis views to establish the spatial relationship of aorta and pulmonary artery. The aorta is typically anterior and leftward of the pulmonary artery. Use multiple nonconventional planes to visualize additional defects, valve morphology and function
Apical views	Detailed systemic RV size and function assessment. RV is identified by moderator band, apical displacement and septal attachments of it’s AV valve. Assess LV size and function (usually crescent-shaped/compressed by systemic RV) Atrioventricular connection RV: Assessment of tricuspid valve morphology, inflow and regurgitation Pulmonary vein Doppler when regurgitation is moderate to severe Atrioventricular connection LV: assess mitral regurgitation CW mitral regurgitation for LV systolic pressure (representing pulmonary systolic pressure only when pulmonary stenosis is absent) Ventriculo-arterial connection (normally aorta is positioned leftward and anterior to the PA however, there is a wide variability in the spatial relationship between the great vessels) Apical 5 chamber view superior tilting for LV- LVOT- PA connection Apical 5 chamber view extensive superior tilting for RV-RVOT-Ao connection Pulmonary/LV outflow: assess for gradient (sub-valvular and valvular) assess pressures from pulmonary regurgitation velocity Aorta/RVOT: assessment of aortic valve function assessment aortic regurgitation LA and RA size
Suprasternal views	Retrograde diastolic flow in descending aorta

ccTGA Reports

Key points to include in transthoracic echo report:

• Systemic RV size (serial comparison) and systolic function
• Systemic tricuspid valve anatomy and function
• Aortic valve function
• Sub pulmonary ventricular size & function
• Sub pulmonary outflow anatomy, especially for subvalvular pulmonary stenosis.

Key views for ccTGA

Figure 1: Apical 4 chamber view – for assessment of the cardiac crux & ventricular morphology. (Left) AV discordance, (right) zoomed in view of the cardiac crux showing reversed offset

LV

RV

Figure 2: PSAX view. (left) side by side orientation commonly seen in ccTGA, (right) both great arteries are seen in short axis, with the aorta anterior and to the left of the pulmonary artery

Figure 3: Ebstein-like tricuspid valve seen in ccTGA

Echocardiographic Assessment of Fontan/TCPC repairs

The following protocol for echo in adult patients following Fontan or TCPC procedure is intended as a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included where valid. It highlights areas of interest in each view specific to Fontan or TCPC evaluation.

Background:

The terms ‘Fontan Operation’ & ‘Total Cavopulmonary Connection’ (‘TCPC’) indicate a concept of circulatory flow rather than a specific type of operation. There are several surgical techniques used to achieve the same outcome.

The main aim of the Fontan circulation is to separate pulmonary & systemic circulations by removing the systemic venous return & its deoxygenated blood from the heart. A single ventricle (or functional single ventricle) often pumps both the systemic and pulmonary circulations. In many cases, the native anatomy also involved a single ventricle physiology.

In Fontan physiology:

• IVC flow is channelled directly to the pulmonary artery and so the circulation bypasses the sub-pulmonary ventricular pump which is small and rudimentary in many cases.
• Multiple step operations are required usually consisting of a Glenn followed by completion of the TCPC.

Bidirectional Glenn operation:

• the SVC is disconnected from the right atrium and redirected into the right pulmonary artery, which remains confluent, hence flow is bidirectional – to both left and right pulmonary arteries.
• Where a left SVC persists, a left-sided SVC-LPA anastomosis can be performed, so creating a bilateral bidirectional Glenn.
• A Glenn operation is not always associated with a complete TCPC. It is sometimes used in isolation e.g.. repair of Ebstein’s anomaly to improve flow to the pulmonary arteries and to unload a small right ventricle. This is also known as a one-and-a-half ventricular repair.

Diagram 1. Bidirectional Glenn operation with confluence of the pulmonary arteries. Diagram from Popelová et al. Congenital Heart Disease in Adults, 2008.

Fontan or TCPC – Are they the same?

Diagram 2 a) An atriopulmonary Fontan, b) Lateral tunnel TCPC, c) extracardiac TCPC. Diagram from Marc R. de Leval & John E. Deanfield Nature Reviews Cardiology 7, 520-527 (September 2010)

1. Atriopulmonary (AP) Fontan

An AP Fontan operation usually describes a direct AP connection by opening the right atrial appendage directly into the main pulmonary artery with no artificial tubes/patches. If a tricuspid valve or atrial septal defect was present, they were both patched closed, and the main pulmonary artery was disconnected often about 1cm above the pulmonary valve. It is sometimes performed with a Glenn operation or, the SVC is left to drain normally into the right atrium. The AP Fontan operation is no longer performed in infants due to its undesirable long term effects of right atrial distension leading to arrhythmias, thrombus & pulmonary venous obstruction.

Post operative sequelae specific to AP Fontan:

• Right atrial dilatation leading to arrhythmias and/or thrombus formation
• Pulmonary venous obstruction
• Narrowing of anastomosis site.

2. Lateral tunnel TCPC

A lateral tunnel TCPC refers to a tunnel (Gore-Tex/Dacron) inserted into the right atrium which directs blood from the inferior vena cava through the right atrium and into the right pulmonary artery. It allows the right atrioventricular valve to contribute to the systemic circulation. In the apical 4 chamber view, a circular structure is noted in the right atrium. A bidirectional Glenn is performed to carry SVC flow directly to the right pulmonary artery. Fenestration in the systemic atrium is performed at the time of operation if the pulmonary vascular resistance is borderline high. The fenestration allows for offloading of increased pressure within the conduit and is vital to keep the Fontan circulation functional. The gradient of the fenestration represents the difference between pulmonary artery & right atrial pressure (i.e. the transpulmonary gradient, which is determined by the PVR) and should usually be 5-8mmHg. Fenestrations are sometimes closed with septal occluder devices later in life if they cause ongoing cyanosis.

Post operative sequelae specific to lateral tunnel TCPC:

• Narrowing of conduit
• Thrombus in conduit
• Spontaneous closure of fenestration if present

3. Extracardiac TCPC

An extracardiac TCPC is a conduit which, like a lateral tunnel, directs blood from the inferior vena cava into the right pulmonary artery, however it is not within the atrial cavity, and so allows both the right atrium and right atrioventricular valve to contribute towards the systemic circulation. It is the current approach and it is hoped that it will reduce the incidence of atrial arrhythmias. A bidirectional Glenn is also performed. The extracardiac approach allows for better streamlining of blood flow from the IVC directly superiorly to the right pulmonary artery.

Indication of Fontan/TCPC:

• Any pathology where either ventricular chamber is hypoplastic & unlikely to successfully support either a pulmonary or systemic circulation on its own. This includes, but is not restricted to, tricuspid or mitral atresia.
• Any pathology where atrioventricular valve chordae straddle the septum, preventing VSD closure and therefore also preventing biventricular repair. This includes, but is not restricted to, double inlet ventricles, AVSDs.

Post-operative Sequelae common to all surgical techniques

• Ventricular dysfunction, systolic and diastolic.
• Complications with conduits – narrowing, obstruction, leaks, thrombus formation
• Atrioventricular valve and /or aortic valve regurgitation which increases systemic ventricular volume loading and pulmonary (Fontan) pressures.
• Restrictive VSD in patient with tricuspid atresia or double inlet LV with VA discordance. Haemodynamic effect of restrictive VSD is similar to that of sub-aortic stenosis.

Imaging protocol for Fontan/TCPC repair

Imaging Window	Assessment particular to Fontan/TCPC
Subcostal view	Assess situs, cardiac position and direction of apex Assess hepatic veins for dilatation and IVC collapse (2D & Doppler) Assess TCPC patency by following IVC flow Assess SVC drainage (in AP Fontan) Exclude RA or conduit thrombus
Apical views	Establish AV and VA connection Ventricular function assessment Assess AV & aortic valve function Exclude restrictive ASD or VSD where applicable Diastolic function assessment –ventricular inflow and pulmonary venous inflow, for serial comparison Exclude pulmonary venous compression Assess TCPC patency, fenestration size & mean gradient Exclude intracardiac or intraconduit thrombus
Parasternal views	Assess ventricular size where possible for serial comparison Assess ventricular morphology Establish VA connection Exclude restrictive VSD Exclude thrombus Valvular assessment Assess pulmonary arteries in SAX views Assess atriopulmonary connection and TCPC patency when possible, including PW Doppler to identify respiratory variation of blood flow.
Suprasternal views (including supraclavicular views).	Assess Glenn patency Assess TCPC patency at pulmonary artery end where possible, using PW Doppler to identify respiratory variation. Exclude pulmonary branch stenosis and coarctation Assess for aorto-pulmonary collateral flow

Single ventricle reports:

Key points to include in transthoracic echo report:

• A clear description of anatomy is required using the sequential segmental analysis
• Ventricular function
• Valvular function
• Any obstruction – across septal defects, valves, vessels or conduits
• Patency of connections
• Thrombus
• Fenestration gradient if present

Assessment of single ventricular function:

• Conventional parameters for assessment of either left or right ventricular function are not applicable due to the unique geometry of the single ventricle +/- contribution of the

rudimentary chamber.

• In situations where the single ventricle is a morphological left ventricle and maintains its basic shape, e.g. tricuspid atresia, Simpson’s biplane EF can still be useful.
• Outside of visual estimation, fractional area change may be the most reliable method for serial assessment as it makes no geometric assumptions.
• Other methods which do not rely on geometry may be useful:
  • Myocardial performance index
  • Isovolumic acceleration time
  • Systolic to diastolic (S:D) ratio from AV valve Doppler

Assessment of Connections:

The normal Doppler profile of flow in a Glenn or TCPC depends on the type of surgery performed. The general principles for both connections are the same. Optimisation of colour flow scales (low Nyquist limit) & spectral Doppler (scale & low velocity filter settings) is strongly recommended.

Figure 1 Normal Glenn flow in AP Fontan:

Note that after the p wave, flow reversal is noted in the Glenn connection, due to a transient rise in right atrial pressure resulting from contraction of the right atrium. Flow is low velocity and phasic, returning to the baseline with every cardiac cycle.

Figure 2 Effect of the respiratory cycle:

It should be noted that Fontan circulations are driven by both the cardiac cycle and the respiratory cycle. Respiratory variation in flow in the connections is considered as a helpful adjunct to help the circulation. During inspiration, the negative pressure is created in the intrathoracic cavity, which helps to ‘suck’ blood into the pulmonary circulation.

Figure 3 Conduit stenosis:

In this example, there is a continuous gradient between

the non-pulsatile superior vena cava and the right atrium. This

suggests a degree of partial obstruction. Complete obstruction

will result in no forward flow.

 

5 important considerations for comprehensive echocardiographic assessment

of patients following Fontan/TCPC operations

1. Know & understand the original anatomy
   • The group of patients selected for TCPC is heterogeneous. Knowing if holes should be open or closed, if they are unimportant or vital, can make life-saving differences to theinterpretation of the examination.
2. Read the surgical notes
   • There are 3 main operations which are seen in adult patients, but beware that variations are common.
   • It is important to know which connections have been made (e.g. Björk procedure or RA to RV Fontan).
   • And beware of the 3^rd connection (most likely in the setting of a persistent left SVC).
3. Understanding normal relationships helps to find connections
   • To find the conduits requires an excellent command of 3-dimensional spatial orientation and echo acoustic windows. Think in terms of anterior or posterior rather than sticking to conventional echo views.
4. Know how to drive the echo machine
   • Especially colour Doppler scale, gains & spectral Doppler low velocity filters
   • Fontan flow is low and slow. Default machine settings will nearly always fail to see the venous flow.
5. Serial evaluation is the best assessment

• Due to the heterogeneity of the group, the patient is their own best control. Sometimes the changes can be subtle but important. Compare ventricular function, diastolic parameters and valvular regurgitation using side-by-side images from the current and previous exams.

Key views specific to Fontan/TCPC repairs:

To view the proximal end of the IVC connection:

Figure 4 Subcostal short axis view of the IVC end of the conduit. Follow the flow from the IVC as it courses superiorly away from the abdomen (blue flow). Note the significant reduction of colour scale makes the flow easier to follow.

Imaging RA connections in AP Fontan:

Figure 5 Subcostal 4 chamber view with superior angulation. The connection is seen with blue flow travelling away from the right atrium – the AP connection is frequently in close proximity to the usual SVC-RA junction (red flow, not seen in this image).

Imaging the Glenn Connection:

Figure 6 Images of the SVC from the right supraclavicular view. Left) SVC flow is noted travelling inferiorly towards the junction of the Glenn connection with the right pulmonary artery. Right) red colour flow from the distal end of the TCPC is noted flowing superiorly towards the right pulmonary artery [this view not always obtainable]. Note the significant reduction of colour scale makes the flow easier to follow.

Supplementary Echo Acquisition Protocol for

Pulmonary Hypertension associated with

Adult Congenital Heart Disease (PH-ACHD)

The following protocol for echo in adult congenital heart disease patients with pulmonary hypertension is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to pulmonary hypertension.

Background

Pulmonary hypertension (PH) is a haemodynamic and pathophysiological condition defined as an increase in mean pulmonary arterial pressure (mPAP) ≥25 mmHg at rest as assessed by right heart catheterization. PH can be found in multiple clinical conditions. Due to fundamental difference in treatment strategy, it is critical to differentiate pulmonary arterial hypertension (PAH) from pulmonary hypertension due to left heart disease. The former has been defined as mPAP ≥25 and pulmonary arterial wedge pressure (PAWP) ≤ 15 mmHg and a pulmonary vascular resistance >3 Wood units.

Clinical classification

Pulmonary arterial hypertension associated with adult congenital heart disease represents a very heterogeneous population. According to recent guidelines¹, patients can be classified

into the following four major groups:

1) Eisenmenger syndrome.

Includes all large intra- and extra-cardiac defects which begin as systemic-to-pulmonary shunts and progress with time to severe elevation of pulmonary vascular resistance (PVR) and to reversal (pulmonary-to-systemic) or bidirectional shunting; cyanosis, secondary erythrocytosis, and multiple organ involvement are usually present.

2) PAH associated with large systemic-to-pulmonary shunts.

Includes moderate to large defects; PVR is mildly to moderately increased, systemic-to-pulmonary shunting is still prevalent, whereas cyanosis at rest is not a feature. Some of these patients may still benefit from surgical or interventional partial or complete closure of the defect.

3) PAH with small/coincidental defects.

Marked elevation in PVR in the presence of small cardiac defects (usually ventricular septal defects <1 cm and atrial septal defects <2 cm of effective diameter assessed by echo), which themselves do not account for the development of elevated PVR; the clinical picture is very similar to idiopathic PAH. Closing the defects is contra-indicated.

4) PAH after defect correction.

Congenital heart disease is repaired, but PAH either persists immediately after correction or recurs/develops months or years after correction in the absence of significant postoperative haemodynamic lesions.

In addition, there are patients with unilateral or segmental pulmonary arterial hypertension and pulmonary hypertension due to systemic ventricular disease including patients with systemic right ventricle (CCTGA, TGA post atrial switch repair).

Role of Echocardiography

Transthoracic echocardiography is the first-line imaging modality in pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD). Echocardiography provides detailed structural and hemodynamic assessment allowing the detection of previously undiagnosed congenital heart defects as well as infer a diagnosis of pulmonary hypertension (table 1 and 2)². It is also very helpful in differentiating PAH from PH due to left heart disease (figure 1)³. During follow-up of patients with known PH, transthoracic echocardiography is used to image the effects of PH on the heart and to monitor the change in PAP.

Imaging protocol for PH in ACHD

View	Areas of interest	PAH specific measurements
Parasternal views	Overall RV size & function including the anterior wall & outflow tract M-mode for septal motion only Doppler of pulmonary valve Degree of pulmonary regurgitation & estimation of PA mean & end-diastolic pressure Anatomy of main pulmonary artery and proximal branches Tricuspid regurgitation velocity for RV systolic pressure Presence of pericardial effusion Assess for shunt lesions	LV size & wall thickness RV dimension (PLAX) Main PA dimension PR early Vmax PR end Vmax PV Vmax PV Acceleration time PV ejection time PV VTI TR velocity RV and LV end systolic dimension ratio – figure 2 LV eccentricity index
Apical views	Detailed LV systolic function assessment Detailed LV diastolic function assessment Detailed RV size and function assessment (qualitative [compared to LV size] & quantitative). Ensure RV focussed view is used for RV dimensions RA size Tricuspid valve assessment Assess for shunt lesions	LV basal dimension RV basal, mid, length dimensions RA area RA volume LA volume MV & TV E velocity MV & TV A velocity TV inflow duration– figure 3 TR velocity TR duration LV lateral M-mode – MAPSE LV septal M-mode – Septal APSE RV lateral M-mode – TAPSE LV lateral S’, E’, A’ velocity LV medial S’, E’, A’ velocity RV lateral S’, E’, A’ velocity
Subcostal views	Assess IVC size & collapse to assess RA pressure Hepatic venous Doppler to assess for increased A wave or flow reversal Pericardial effusion	IVC dimension at end expiration
Suprasternal views	Assessment of branch pulmonary arteries

Table 1: Echocardiographic probability of pulmonary hypertension in

symptomatic patients with a suspicion of pulmonary hypertension

Peak TR velocity* (m/s)	Presence of other echo PH signs	Echo probability of PH
≤2.8 or not measurable	No	Low
≤2.8 or not measurable	Yes	Intermediate
2.9-3.4	No
2.9-3.4	Yes	High
>3.4	Not required

*Peak TR velocity is valid in the absence of pulmonary outflow obstruction. Table adapted from Galie N. et al: 2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension. European Heart Journal (2015) 37, 67–119

Table 2: Echocardiographic signs suggesting pulmonary hypertension used to assess the probability of pulmonary hypertension in additions to tricuspid regurgitation velocity measurement.

A: The ventricles	B: Pulmonary artery	C: Inferior vena cava & right atrium
RV/LV basal diameter ratio >1.0	RV outflow Doppler acceleration time < 105ms &/or midsystolic notching	IVC dimension >21mm with decreased inspiratory collapse (<50% with a sniff or <20% with quiet inspiration)
Flattening of the IVS (LV eccentricity index >1.1 in systole &/or diastole)	Early diastolic PR velocity > 2.2m/s	RA area (end-systole) > 18cm2
	PA dimension > 25mm
*Echocardiographic signs from at least different categories (A/B/C) from the list should be present to later the level of echocardiographic probability of pulmonary hypertension

Adapted from Galie N. et al: 2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension. European Heart Journal (2016) 37, 67–119

PH in ACHD reports

Key points to include in transthoracic echo report:

• Estimate of pulmonary pressure using TR velocity & pulmonary Doppler
• RV size & function
• Septal motion
• Hepatic vein status
• Any contributing valve disease
• LV diastolic function assessment is crucial and may determine management strategy

Figure 1: Examples of typical pre- and postcapillary PH:

Adapted from D’Alto M et al. Echocardiographic Prediction of Pre- versus Postcapillary Pulmonary Hypertension J. Am Soc Echo 2015, 28: 108-15 and Jone PN et al, Right Ventricular to Left Ventricular Diameter Ratio at End-Systole in Evaluating Outcomes in Children with Pulmonary Hypertension J. Am Soc Echo Feb 2014;27)

Figure 2: Parasternal short axis view of LV and RV.

RV and LV end-systolic dimensions. Adapted from Jone PN et al, JASE Feb 2014;27

Figure 3 : Continuous wave Doppler recording of tricuspid valve regurgitation:

S = TR duration, d = TV inflow duration. As described in Moceri P el al. Circulation 2012;126:1461-1468 & Alkon J. Am J Cardiol 2010;106:430-436)

References/further reading

1. Galie N. et al: 2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension. European Heart Journal (2016) 37, 67–119

2. D’Alto M et al. Echocardiographic Prediction of Pre- versus Postcapillary Pulmonary Hypertension J. Am Soc Echo 2015, 28: 108-15

3. Jone PN et al, Right Ventricular to Left Ventricular Diameter Ratio at End-Systole in Evaluating Outcomes in Children with Pulmonary Hypertension J. Am Soc Echo Feb 2014;27

4. Moceri P el al. Echocardiographic Predictors of Outcome in Eisenmenger Syndrome Circulation 2012;126:1461-1468

5. Alkon J, Hupl T, Manlhiot C, et al. Usefulness of the right ventricular systolic to diastolic duration ratio to predict functional capacity and survival in children with pulmonary arterial hypertension. Am J Cardiol. 2010;106:430–436.

Basic Report Template for Adult Congenital Echocardiography – Normal heart

Situs solitus, levocardia, atrioventricular & ventriculo-arterial concordance.

Normal right ventricular size and systolic function.

Normal right atrial size. The interatrial septum appears intact.

The pulmonary valve functions normally.

There is * tricuspid regurgitation. The estimated right ventricular systolic pressure is *mmHg if right atrial pressure is *mmHg.

Normal left ventricular size and ejection fraction. Biplane EF = %. Normal wall thickness & diastolic filling parameters.

Normal left atrial size.

The aortic valve is trileaflet and functions normally. Normal aortic root & ascending aorta. There is normal flow through a left aortic arch.

The mitral valve is structurally and functionally normal.

No evidence of pericardial effusion.

CONCLUSION

Normal LV size & ejection fraction, EF *%.

Normal RV size & systolic function.

Estimated RVSP *mmHg.

No significant valvular disease.

Supplementary ACHD Echo Acquisition Protocol for

Atrial Septal Defects

The following protocol for echo in adult patients with atrial septal defects (ASDs) is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to unrepaired & repaired ASDs.

Background

• ASD represents one of the most common congenital heart disease lesions in adult patients.
• It is not uncommon that it remains undiagnosed until adulthood since patients may remain asymptomatic or only mildly symptomatic for a long time.

1

2

3

4

5

Diagram showing different types of ASDs

1. Sinus venosus (SVC type)
2. Secundum ASD
3. Primum ASD
4. Sinus venous (IVC type)
5. Unroofed coronary sinus ASD.

Diagram adapted from Popelova et al

• The secundum ASD – located within the region of the oval fossa – is by far the most common type (approximately 80% of ASDs).
• The “primum ASD” – located near the crux of the heart – accounts for approximately 15% of ASDs. It belongs to the group of atrioventricular septal defects (partial AVSD or partial AV canal) and is typically associated with AV-valve abnormalities and will be addressed in the atrial ventricular septal defect protocol.
• The sinus venosus defects are located at the regions connecting atrium and the caval veins.
  • The superior sinus venosus defect is much more common (~5% of ASDs) than the inferior one (<1%) and is typically associated with partial (sometimes complete) drainage of the right pulmonary veins to the SVC and right atrium.
  • Sinus venosus defects can be difficult to visualise on transthoracic echo, so often transoesophageal echo is necessary.
• The unroofed coronary sinus is a rare form of ASD, characterised by a communication between the coronary sinus and the left atrium. It is almost always associated with a persistent left caval vein draining to the roof of the left atrium.

Common associations

• Right ventricular volume overload
• Elevated pulmonary artery pressure
• Secondary tricuspid regurgitation
• Right atrial dilatationAnomalous pulmonary venous connection (sinus venosus and secundum defects)Persistent left SVC (unroofed coronary sinus)

Treatment

Defect can be closed either via:

• Surgical patch
• Direct suture (if small)
• Percutaneous occluder

Residual haemodynamic lesions and complications in repaired ASDs

• Residual shunt
• Residual RV dilatation and/or dysfunction
• Residual elevated pulmonary artery pressure
• Pulmonary venous obstruction
• Septal occluder erode to aortic root or atrial wall
• Thrombus (in region of device)
• Tricuspid regurgitation

Imaging protocol for atrial septal defect

Subcostal views	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapse to estimate RA pressure Hepatic venous Doppler to assess for venous flow pattern or flow reversal In 4 chamber view, sweep through from posterior to anterior aspect of the interatrial septum checking for defects. Add reduced colour Doppler scale and repeat. In short axis view, sweep from patient’s right to left (IAS to apex). Add reduced colour Doppler scale and repeat. Bicaval view: modified short axis view demonstrating IVC & SVC inflow. Add reduce colour scale and repeat. Rim dimensions. Maximum diameter ASD in multiple planes RV size(compared to LV size) and function Check pulmonary venous anatomy, especially for anomalous connection into SVC near RA junction.
Parasternal views	Overall RV function including the anterior wall & outflow tract Ventricular septal motion for RV volume & pressure overload Pulmonary valve anatomy & function, degree of PR Doppler of pulmonary valve & estimation of PA mean & end-diastolic pressure Anatomy of main pulmonary artery and proximal branches Aortic rim dimension Pulmonary venous return Tricuspid regurgitation. CW for RV systolic pressure Dilatation of coronary sinus
Apical views	Detailed LV function assessment. Assess aortic valve function Detailed RV size and function assessment (qualitative compared to LV size & quantitative). RA size Anterior angulation to assess anatomy and function of right ventricular outflow Assess tricuspid valve function Pulmonary venous return Posterior angulation to coronary sinus
Suprasternal views	Assessment of pulmonary venous return where possible (crab view) Assessment of branch pulmonary arteries Assessment of right +/- left-sided SVC in the setting of dilated coronary sinus

ASD Reporting:

Key points to include in transthoracic echo report:

• ASD
  • Location
  • Measurement
  • Direction of shunting
• RV size/degree of dilatation and systolic function
• RVSP or mean PA pressure
• Presence of functional TR
• Associated lesions specific to type of ASD
• LV diastolic function
• For secundum ASD and suitability of percutaneous closure:
  • Atrial septal rims are important. Comment on presence of absence of posterior rim if possible.
  • Normal pulmonary venous drainage is also important
• Post repair:
  • RV size & function as a function of remodelling
  • Patch/occluder integrity and any residual leak
  • Mitral & tricuspid regurgitation
  • RVSP
  • LV diastolic function.

Key views specific to ASD patients:

Figure 1 Subcostal long (A) and short (B) axis view of a secundum ASD (shown as *)

Figure 2 Subcostal long and short axis view of a secundum ASD taken with bi-plane imaging.

Figure3 If subcostal imaging is of poor quality, a parasternal fore-shortened view (A) or a low or high right parasternal view (B) are two good options for ASD (*) visualization

Figure 4: SVC type sinus venosus ASD seen in apical 5 chamber view (left) & zoomed views (right) (arrow)

Figure 5: SVC type sinus venosus ASD seen in zoomed subcostal view with slight clockwise rotation (left) SVASD denoted by asterisk & (right) asterisked arrow demonstrates left to right flow. Plain arrow shows normal SVC flow.

A B

Figure 6 Visualization of the 4 pulmonary veins:

From the apical 4 chamber:

A; right upper pulmonary vein

B; right lower pulmonary vein

C; left upper pulmonary vein

D;The left lower pulmonary vein is best visualized from the parasternal short axis view

C D

Figure 7

Suprasternal scan showing all four pulmonary veins entering the left atrium.

Supplementary ACHD Echo Acquisition Protocol for

Ventricular Septal Defects

The following protocol for echo in adult patients with Ventricular Septal Defects is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to unrepaired and repaired VSDs.

Background

• VSDs represent the most common congenital cardiac malformation (approx. 30% of congenital heart defects).

Diagram: Anatomic location of ventricular septal defects (VSD), viewed from the right ventricle.

1 – Doubly committed VSD;

2 – perimembranous VSD

3 – inlet VSD

4 – muscular central VSD

5 – muscular apical VSD

6 – muscular marginal VSD.

SCV – Superior vena cava; ICV – inferior vena cava; AO – aorta; PA – pulmonary artery

Diagram from Popelova et al.

• Depending on the location of the defect within the ventricular septum and the relationship to the membranous septum, perimembranous defects, doubly committed defects (also called supracristal or subarterial outlet VSDs) and muscular defects are distinguished.
  • Perimembranous defects border the membranous septum and represent the most common form (approx. 80%). These VSDs are subaortic and subtricuspid and are characterized by fibrous continuity between the aortic and the tricuspid valve. However, the defect can extend into the inlet or outlet part of the ventricular septum.
  • Muscular VSDs account for approx. 15-20% of VSDs in adults and are completely surrounded by ventricular musculature. They can occur within the inlet, apical (trabecular) or outlet portion of the RV. They may be multiple.
  • Doubly committed or outlet VSDs are characterized by a defect in the fibrous continuity between the aortic and pulmonary valves and are located directly beneath the semilunar valves. Doubly committed VSDs are typically associated with aortic cusp prolapse (usually the right coronary cusp) and AR.
  • Inlet or AVSDs: see AVSD echo protocol.
  • Gerbode defects: deficiency of the atrioventricular membraneous septum and represents a shunt from the left ventricle to the right atrium. These defects can be native or can occur post AVSD repair.
• Disruption of normal aortic valve function, namely regurgitation due to prolapsing of the right or non-coronary cusp is a recognised complication of doubly committed VSDs and also (but less commonly) in perimembranous outlet VSDs.
• A double chambered RV may develop or progress during adult life; especially in perimembranous VSDs. Particular attention is required to not overlook this lesion.
• In cases where VSDs become haemodynamically significant, it is left atrium and left ventricle which are affected by volume overload, in contrast to the right heart overload seen in atrial septal defects.

Common associations

• Left atrial and ventricular volume overload
• Elevated pulmonary artery pressure, or Eisenmenger’s physiology
• Aortic sinus prolapse and aortic valve regurgitation
• Double-chambered right ventricle

 

Surgical or trans-catheter approaches

• Surgical patch
• Percutaneous occluder

Residual haemodynamic lesions and complications in repaired VSD

• Residual shunt
• Persistent LV dilatation and systolic or diastolic dysfunction
• Residual elevated pulmonary artery pressure
• Residual aortic valve abnormalities and regurgitation
• Double-chambered RV
• Device location and interference with surrounding structures

VSD Haemodynamics

The peak pressure gradient across the VSD is obtained with CW Doppler and is useful in estimating PA systolic pressure (in the absence of RV outflow obstruction) when compared with the patient’s systolic blood pressure. In the absence of LV outflow obstruction, the systolic blood pressure is used as a surrogate for left ventricular systolic pressure. It is important to exclude pulmonary hypertension which can have a significant impact on treatment. This method of estimating RV pressure is particularly useful in cases where the VSD jet is directed towards the tricuspid valve and so contaminates the TR Doppler signal.

RVSP = BP_systolic – peak VSD gradient

A restrictive VSD describes the haemodynamic situation of the defect rather than referring to the anatomy. The term is used when a high pressure difference between left & right ventricles is maintained suggesting that RV pressure is normal and so the amount of blood passing through the defect is small.

In adults with increased LV diastolic pressure, left to right shunt may also occur during diastole which can contribute to further left heart volume overloading

Imaging protocol for ventricular septal defect

Subcostal views	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapse to estimate RA pressure Hepatic venous Doppler to assess venous flow pattern and flow reversal Identification of VSD location and size (perimembranous, muscular, doubly committed) Examine for multiple defects Retrograde flow in abdominal aorta (in cases where significant AR present)
Parasternal views	Identification of VSD location: 2D & colour Doppler sweeps of entire septum PLAX (perimembranous inlet/outlet, muscular) PSAX at level of great vessels 9-12 o’clock perimembranous VSD 12-3 o’clock outlet VSD PSAX all levels (muscular VSDs may require atypical views) 2D measurement of defect Peak CW Doppler gradient of VSD flow to assess RV pressure Assessment of Aortic valve cusp prolapse Colour Doppler assessment for AR Pulmonary valve anatomy & function, degree of PR Doppler of pulmonary valve & estimation of PA mean & end-diastolic pressure Anatomy of RVOT and main pulmonary artery and proximal branches Doppler of RVOT for double-chambered RV (interference of VSD jet may complicate interpretation) Assessment tricuspid valve (aneurysmal transformation of VSD, pseudo aneurysm) Tricuspid regurgitation. CW for RV systolic pressure (if increased TR velocity, then need to exclude double-chambered RV) LV size
Apical views	Identification of VSD location and size: apical 4 & 5 chamber views (perimembranous, inlet/outlet, muscular) Left atrial size Detailed LV function assessment. Assessment of aortic valve function RV size and function Assessment of tricuspid valve function and regurgitation (be aware that VSD jets can sometimes be confused with the TR jet depending on VSD jet direction).
Suprasternal views	Retrograde diastolic flow in descending aorta in the presence of AR.

VSD Reporting

Key points to include in transthoracic echo report:

• VSD
  • Location
  • Measurement
  • Direction of shunting
  • Systolic pressure gradient
  • Presence of diastolic flow >1m/sec suggests diastolic disease
• LV size/degree of dilatation and systolic function
• LA size
• RVSP or mean PA pressure
• Associated lesions specific to type of VSD
• For perimembraneous VSD, aortic valve function
• If associated with a double chambered RV, then gradient within the RV.

Post repair:

• LV size & function as a function of remodelling
• VSD patch/occluder integrity and residual leaks
• Presence of aortic valve regurgitation

Key views specific to VSD patients:

Fig. 1

1. parasternal long axis view of a subarterial VSD. Note that the right aorta sinus is already showing signs of prolapse. The flow through VSD shows clearly that the defect is subaortic.
2. Parasternal short axis view systolic frame: showing the high jet velocity crossing the VSD and the laminar flow in the RVOT
3. Parasternal short axis view diastolic frame: Absent septal tissue between aortic valve and pulmonary valve is characteristic of doubly committed sub-arterial VSD. The jet through VSD is very close to the pulmonary valve. Confirming that it is a subarterial VSD.

Fig. 2

Parasternal long axis view (zoom mode) showing a perimembranous VSD with:

1. aneurysmal formation (pseudo aneurysm), tricuspid valve tissue spontaneously closing the defect.
2. high velocity colour flow Doppler through the defect

Fig 3

Prolapse of the right coronary sinus (*) through a subarterial VSD sealing the VSD completely.

Fig. 4

Apical four chamber view

1. Mid-muscular VSD (*)
2. High velocity colour flow Doppler through the defect. The direction of this jet can cause problems for the correct interpretation of the CW Doppler from the tricuspid regurgitation.

Fig 5

Focused apical RV view

1. Multiple mid muscular VSDs (*)
2. Colour flow Doppler confirming the defects and showing moderate tricuspid regurgitation.

A B C

Fig 6. With the use of iRotate this unorthodox view can be acquired

1. Gives the landmarks with an asterisk marking a subvalvular narrowing. This results from the jet lesion of a small VSD and form DCRV.
2. Early systole the residual VSD jet is seen entering the RV-RVOT
3. Late systole high velocity jet from the DCRV obstruction is shown. The severity of the obstruction can also be calculated using the Vmax from the tricuspid regurgitation jet velocity.

Supplementary ACHD Echo Acquisition Protocol for

Atrioventricular Septal Defect

The following protocol for echo in adult patients with AVSD is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to repaired AVSD.

Background

• AVSDs are characterized by a common atrioventricular junction with deficient atrioventricular septation.
• This congenital heart defect is particularly common in patients with Down syndrome (prevalence of AVSD around 30%).
• Anatomic characteristics are
  • a common ovoid shaped atrioventricular junction,
  • a defect of the membranous atrioventricular septum,
  • a 5 leaflet common valve (left and right mural leaflet, right antero-superior leaflet, superior and inferior bridging leaflet),
  • an un-wedged aorta with an elongated LVOT (i.e. “gooseneck deformity”).

Diagram: Atrioventricular septal defect (AVSD):

1. normal relation between interatrial septum (IAS), atrioventricular septum (AVS), interventricular septum (IVS), and septal cusps of tricuspid (T) and mitral (M) valves;
2. incomplete AVSD (atrial septal defect type

primum)

1. complete AVSD (complete atrioventricular septal defect).

Diagram adapted from Popelova et al.

• Functionally, AVSDs can be partial with shunting only at the atrial level (also called primum ASD or partial AVSDs) or complete with shunting at atrial and ventricular level (CAVSDs).
  • Partial AVSDs present with fused superior and inferior-bridging leaflets and attachment of these bridging leaflets to the scooped out crest of the ventricular septum. These patients, therefore, have 2 valve orifices with trileaflet left AV valve (albeit with a common AV junction). As the AV valves are not morphologically true mitral and tricuspid valves, they are referred to as left and right AV valves.
  • There is a continuum between partial and complete forms. There may be a VSD that is completely or partially covered by valve tissue forming an aneurysmal basal inlet ventricular septum with or without a restrictive VSD. This is called intermediate AVSD and may – as partial AVSD – be encountered unrepaired in adults.
  • Complete AVSDs present in adult life either after repair or – if unrepaired – with Eisenmenger physiology.
• After repair, atrioventricular valve malfunction (frequently regurgitation, less commonly stenosis) requires particular attention. Morphology and malfunction mechanism require detailed analysis. Residual ASD and/or VSD, LVOT obstruction, LV and RV abnormalities, and PAP elevation must be excluded or identified.

Common associations

• See ASD protocol
• AV-valve abnormalities and LVOT obstruction
• Double orifice left AV valve
• Anomalous papillary muscles
• Parachute left AV valve
• Left ventricular volume overload
• Pulmonary arterial hypertension or Eisenmenger syndrome
• Displacement of the AV node with associated arrhythmias

Residual haemodynamic lesions and complications in repaired AVSD

• Residual shunt (atrial and ventricular level)
• RV and LV dilatation and dysfunction
• Residual elevated pulmonary artery pressure
• Left-sided AV valve regurgitation, often through the closure line between superior and inferior bridging leaflet.
• Right-sided AV valve regurgitation
• LVOT obstruction

Imaging protocol for atrioventricular septal defect

Subcostal views	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapse to assess RA pressure Hepatic venous Doppler to assess venous flow pattern and systolic flow reversal from significant right AV valve regurgitation Residual shunt (VSD, ASD, LV-RA, RV-LA shunt) maybe multiple RV size and function Retrograde flow in abdominal aorta (in cases where > moderate AR present)
Parasternal views	Shunt or residual shunt (VSD,ASD,LV-RA, RV-LA shunt) maybe multiple Left AV valve evaluation ( thickening, trileaflet, abnormal chordae) Severity and mechanism of left AV valve regurgitation (multiple jets possible) Assessment of papillary muscles (number, proximity to each other) Assess for double orifice left AV valve. Right AV valve evaluation (morphology) Severity and mechanism of right AV valve regurgitation CW Doppler flow velocity. LVOT obstruction morphology (accessory chordae, leaflet insertion, ridge) Colour Doppler (identify area of obstruction) Aortic valve morphology and quantify aortic regurgitation Doppler of pulmonary valve; degree of PR & estimation of PA mean & end-diastolic pressure Tricuspid regurgitation. CW Doppler for RV systolic pressure LV and LA dimension
Apical views	Detailed LV function assessment. Shunt or residual shunt (VSD,ASD,LV-RA, RV-LA shunt) maybe multiple Aortic valve morphology and quantify aortic regurgitation LVOT obstruction (PW at multiple levels to identify the level of obstruction) Left AV valve evaluation ( thickening, septal commissure, abnormal chordae) Severity and mechanism of left AV valve regurgitation (multiple jets possible) CW for left AV valve gradient (especially after repair) Right AV valve evaluation (morphology) Severity and mechanism of right AV valve regurgitation Detailed RV size and function assessment (qualitative compared to LV size & quantitative). LA and RA size
Suprasternal views	Assessment aortic valve Doppler gradient and regurgitation

AVSD Report Template

Key points to include in transthoracic echo report:

• Complete, partial or transitional AVSD
• Size of atrial and ventricular components
• Direction of shunting for both components
• AV valve chordal anatomy (if considered for surgery, especially straddling)
• AV valve regurgitation
• Estimate of pulmonary pressure
• Other associated lesions
• Ventricular size & function

Post repair

• Residual ASD or VSD
• Residual LV-RA shunting (Gerbode like defects)
• Left & right AV valve function
• Left & right ventricular size & function
• Estimate of pulmonary pressure
• Evaluation of associated lesions e.g. LV outflow obstruction

Key views specific to AVSD patients:

Fig 1. A: Parasternal long axis RV inflow view shows the atrial septal defect (asterisk) with Clear visualization of AV valves, on the same level. B. Parasternal short axis view showing the three leaflets (asterisk) of the left AV valve. Arrow indicates the commissure between anterior and posterior bridging leaflets

Fig 2. A: Apical 4c view AV valves are on the same level. Arrow shows the small atrial septal defect. LV and LA are dilated due to sever left AV regurgitation. B. Zoom of the AV junction showing clear chordae attachments of the superior bridging leaflet on to the septum (asterisk) . No ventricular shunt was present. Arrow shows the small atrial septal defect.

Figure 3: complete AVSD apical view in diastole

Figure 4 Partial AVSD/primum ASD. (Left) shows the primum ASD in diastole. (Right) shows no offset of the individual AV valves

Figure 5: (left ) trileaflet left AV valve & (right) regurgitation arising from the anterior closure line /line of apposition. This is seen in partial AVSD and also in repaired common AVSD.

Supplementary ACHD Echo Acquisition Protocol for

LV outflow obstructions

The following protocol for echo in adult patients with LV outflow obstructions, including subvalvular, valvular, supravalvular stenoses and coarctation and is intended as a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to LV outflow evaluation.

Background:

This document incorporates the following lesions:

• Subvalvular aortic stenosis, including subaortic membranes
• Valvular stenosis, including bicuspid & dysplastic aortic valves
• Supravalvular stenosis, including hourglass narrowings and hypoplastic ascending aorta
• Coarctation of the aorta

Diagram: Aortic coarctation: relationship to the origin of the left subclavian artery is important to identify. Diagram adapted from Popelova et al

Common associations:

• Subaortic membrane
  • bicuspid aortic valve, coarctation, supramitral ring, parachute mitral valve (when all features are present, this condition is collectively referred to as Shone syndrome)
  • aortic regurgitation
• Bicuspid aortic valve – ascending aorta dilatation, coarctation, Turner syndrome
• Supravalvular stenosis – Williams syndrome
• Coarctation – bicuspid aortic valve

Common sequelae:

• Aortic regurgitation
• LV hypertrophy
• LV systolic & diastolic dysfunction
• In severe cases, pulmonary hypertension, secondary to LV diastolic dysfunction.
• Clinically in coarctation, reduced femoral pulses or arm-leg blood pressure gradient

Tips & Tricks:

1. Subaortic stenosis:

• Assess for cause of obstruction: e.g. subaortic membrane/ridge/chordae crossing outflow tract, diffused tunnel like narrowing or basal septal hypertrophy
• Turbulent flow through LVOT can damage aortic valve leaflets and cause aortic regurgitation
• Assess timing of flow – often a dynamic obstruction peaks in late systole whereas a fixed obstruction peaks in mid systole. This has important implications for patient management.

1. Aortic valve stenosis:

• Assess valve anatomy and number of leaflets
• Assess for co-existing aortic regurgitation, often eccentric if bicuspid aortic valve
• Assess aortic root and ascending aorta for dilatation (using higher left parasternal & right parasternal views)
• Use apical, suprasternal and right parasternal windows as minimum attempt to search for best Doppler/blood flow alignment to reflect the true gradient. Bicuspid valve flow is often eccentric. Non-imaging probe is highly recommended.
• Use modified Bernoulli equation to correct gradients if LVOT velocity >1.2m/sec (see below).

1. Supravalvular aortic stenosis:

• Identify level of stenosis e.g. sinotubular junction or in ascending aorta (right parasternal or apical long axis views may be helpful).
• Identify extent of stenosis – discrete or long, tunnel like narrowing (important Doppler considerations-see below)
• Use multiple windows to identify true gradient
• Confirm that aortic valve function is normal.

1. Coarctation:

• Unexplained concentric left ventricular hypertrophy can be the important clue to coarctation.
• Assess descending aorta with CW Doppler, including the non-imaging probe.
• The shape of the CW Doppler signal is more informative than the peak velocity: extension of forward flow into diastole can suggest the presence of severe stenosis and a collateral circulation, which is clinically significant, irrespective of peak gradient. In a normal situation, the cessation of aortic flow will coincide with the end of the T-wave on the ECG. In coarctation, forward flow is seen after the T-wave. This flow is often referred to as a ‘diastolic tail’.
• In long segments of coarctation, the CW Doppler gradient can be unreliable due to the assumptions of the Bernoulli equation being untrue and also the presence of significant collaterals providing an alternative pathway for flow.
• In the suprasternal view, be careful not to confuse ‘double shadows’ given by flow in the left pulmonary artery, which courses in front of the descending aorta
• Assess abdominal aortic flow for systolic blunting and any diastolic continuation of flow
• In the case of extensive collateralization, mild exercise (supine pedalling motion increasing the heart rate to 90-100 bpm) may saturate the collaterals, force flow through the coarctation and reveal the gradient.

Imaging Protocol for LV outflow obstruction

PLAX/RV inflow	LV size & function LV wall thickness Demonstrate LV outflow tract, aortic valve anatomy, number of leaflets, aortic root and ascending aorta Assess valvular function Assess site of stenosis
Apical views	Obtain LVOT VTI with PW Doppler Obtain peak outflow gradients and VTI using CW Doppler (with non-imaging probe) Assess AoV regurgitation Assess level of stenosis Assess ventricular function Assess diastolic function Assess TR for pulmonary hypertension
Subcostal view	Assess abdominal aortic flow profile
Suprasternal views	Assess arch dimensions, site of narrowing, peak gradient, presence of diastolic forward flow. Attempt to demonstrate collaterals if coarctation; may use mild exercise (see tips and tricks) Obtain peak aortic/outflow gradient & VTI from suprasternal notch & clavicular views. Use of non-imaging probe is recommended
Right parasternal	Assess dimensions & contour of ascending aorta Assess peak aortic gradient. Use of non-imaging probe is recommended

Technical considerations:

1. The Simplified Bernoulli equation.

• The simplified Bernoulli equation is used frequently throughout echocardiography and converts a velocity to a pressure gradient using the equation:

ΔP = 4V²

• It is simplified from a much more complex equation which accounts for convective acceleration, flow acceleration and viscous friction. The simplified equation holds multiple assumptions.
• One of the assumptions is that there is no substantial acceleration of proximal flow which is valid when proximal flow is <1.2m/sec.
• In instances when proximal flow is ≥1.2m/sec, the modified Bernoulli equation must be used in order to prevent over-estimation of gradients:

ΔP = 4 (V₂² – V₁²)

where V₂ = peak obstructive gradient (CW Doppler)

& V₁ = velocity proximal to obstruction (PW Doppler)

Case example:

LVOT Vmax 1.6m/sec AoV Vmax 3.1m/s

LVOT peak gradient 10mmHg AoV peak gradient 38mmHg

LVOT mean gradient 7mmHg AoV mean gradient 22mmHg.

In this dataset, the LVOT flow is elevated at 1.6m/sec and is outside the defined ‘negligible’ contribution to the peak aortic velocity as stated in the Bernoulli equation. Therefore, these aortic gradients should be corrected.

Corrected peak AoV gradient = 4 (V₂² – V₁²)

= 4 (3.1² – 1.6²)

= 4 (9.61-2.56)

= 4 * 7.05

= 28mmHg.

Corrected mean gradient = AoV mean gradient – LVOT mean gradient

= 22 – 7

= 15mmHg.

In practical terms, this scenario most commonly arises in both aortic stenosis and in coarctation when the LVOT flow or PW Doppler just proximal to the coarctation has a velocity >1.5m/sec.

1. Long tubular narrowings:

• The Bernoulli equation is valid for discrete, localised obstructions. Where there are long tubular narrowings e.g. hypoplastic ascending aorta or long segments of coarctation, the Bernoulli equation does not accurately reflect the true pressure gradient due to rapid pressure recovery. Echo-derived gradients can appear over-estimated when compared to invasively-derived catheter gradients.

1. Multiple sites of narrowing

• Special caution should be taken in the setting of multiple sites of stenosis e.g. severe AS with coarctation as multiple assumptions of the Bernoulli equation can be violated simultaneously and therefore Doppler gradients become increasingly unreliable. Peak velocity and timing of flow may provide an idea of the gradient but alternative imaging modalities are recommended.

Bicuspid Aortic Valve Reports

Key points to include in transthoracic echo report:

• LV size, function & wall thickness
• Valve anatomy: true bicuspid versus functionally bicuspid, if so name the fused cusps
• Valve function: peak & mean gradients, AVA, indexed stroke volume
• Aortic measurements: LVOT, hingepoint, trans-sinus, sinotubular junction, ascending aorta, arch & isthmus
• Presence of coarctation
• Estimate of pulmonary pressure
• Assess for other associated anomalies

Key Views Specific to LV outflow tract obstructions:

1. Parasternal long and short axis views with aortic root/ascending aorta and view of bicuspid aortic valve.
2. M-mode recording of aortic valve movement in patient with sub-aortic stenosis.
3. Apical 5 chamber showing sub aortic stenosis CFI
4. Apical 5 chamber CW Doppler showing AS signals
5. Suprasternal view with diastolic tail versus normal
6. Abdominal aorta PW Doppler – 1 normal showing early diastolic flow reversal then diastolic forward flow as normal and 2^nd showing a true diastolic tail

Parasternal long axis with subaortic membrane 2D & CFI

A

B

C

D

Figure 1: Subaortic membrane: A) subaortic membrane seen clearly in the outflow tract. LVH. B) turbulent colour flow arising from LVOT. C) apical long axis view showing membrane and LVOT turbulence D) CW Doppler confirms severe outflow tract obstruction

Figure 2. M-mode recording of aortic valve showing mid systolic closure of the aortic valve (arrow) in patient with sub aortic stenosis

Figure 3: Tunnel like sub-aortic stenosis. A) Parasternal view showing diffused narrowing of LVOT with turbulent flow on colour Doppler. B) Apical five chamber view showing hypertrophied muscular tissue causing narrowing LVOT. C) CW Doppler confirms severe outflow tract obstruction

Figure 4. Bicuspid aortic valve. a)Parasternal long axis view showing bicuspid aortic valve and measurement of aortic root dimensions at ventriculo-arterial junction, trans-sinus, ST junction and ascending aorta. b) Parasternal short axis view demonstrating a bicuspid aortic valve during ventricular systole with limited opening orifice.

A

B

C

Figure 5. Coarctation of aorta. A) Supra-sternal view of aortic arch, narrowing at proximal descending aorta (arrow). B) Colour Doppler Mapping showing turbulent flow across the site of coarctation. C) continuous wave Doppler recording in the descending aorta showing increased peak systolic flow velocity with long diastolic tail (arrow) characteristic for significant coarctation of aorta.

A

B

C

Supplementary ACHD Echo Acquisition Protocol for

Ebsteins Anomaly

The following protocol for echo in adult patients with Ebsteins anomaly is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to Ebstein’s patients.

Definition:

• Apical displacement of the septal leaflet of the tricuspid valve into the right ventricle. The posterior leaflet is sometimes also displaced. The leaflets have failed to fully delaminate from the septum and are often dysplastic with thickened, rolled & shortened chordae and under-developed papillary muscles
• Anterior leaflet is elongated and redundant with abnormal chordal attachments directly to the lateral wall.
• “Atrialization” of the basal portion of the right ventricle (aRV) with abnormal ventricular septal motion.

Septal leaflet

Annulus

Posterior leaflet

Anterior leaflet

Coronary sinus ostium

Patent foramen ovale

Fenestrations

Diagram 1 Diagram of Ebstein anomaly. Adapted from Ebstein W. Ueber einen sehr seltenen Fall von Insufficienz der Valvula tricuspidalis, bedingt durch eine angeborene hochgradige Missbildung derselben. Arch Anat Physiol. 1866; 238–255.

Common associations:

• ASD or PFO (bi-directional shunting is common)
• VSD
• Pulmonary atresia with intact ventricular septum
• MV prolapse
• Coarctation of aorta
• LV non compaction

Carpentier’s Classification in Ebstein Anomaly

D.

C.

B.

A.

Diagram 2 Carpentier’s Classification. Type A: the volume of the true right ventricle (RV) is adequate; Type B: a large atrialized component of the RV exists, but anterior leaflet of the tricuspid valve moves freely; Type C, the anterior leaflet is severely restricted in its movement and may cause significant obstruction of the right ventricular outflow tract; Type D, almost complete atrialization of the RV except for a small infundibular component. (Carpentier A, et al. A new reconstructive operation for Ebstein’s anomaly of the tricuspid valve. J Thorac Cardiovasc Surg. 1988;96: 92–101. )

Diagram 3. Different types of Ebstein anomaly. Diagram adapted from Popelova et al.

Celermajer Index in Ebsteins Anomaly

The Celermajer Index (CI) compares the combined right atrial and atrialised right ventricular area to the area of the remainder of the cardiac chambers seen in the apical 4 chamber view and correlates with prognosis in neonates.

Figure 1: Celemajer Index measurements

Celermajer Index = Total area of right atrium + atrialised RV

Total area of functional RV + LA + LV

Celermajer’s echocardiographic grading score: the ratio of the combined area of the right atrium and atrialized right ventricle is compared with that of the functional right ventricle and left heart:

grade 1: ratio <0.5;

grade 2: ratio 0.5 to 0.99;

grade 3: ratio 1.0 to 1.49,

grade 4: ratio >=1.5

A ratio ≥1 in a neonate indicates a very poor prognosis.

(Celermajer DS, et al. Ebstein’s anomaly: presentation and outcome from fetus to adult. J Am Coll Cardiol. 1994;23:170 –176.)

Imaging protocol for Ebstein anomaly

Subcostal views	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapsing Assess atrial septum RV SAX may offer biplane FAC of RV
PLAX/RV inflow	Assess displacement of septal +/- posterior leaflet involvement Assess TR severity Measure LV size TV leaflets seen in RVOT in standard PLAX suggest anterior rotation of the tricuspid orifice
Parasternal short axis	Assess rotation of tricuspid valve closer in position to the pulmonary valve Assess TR severity Assess RVOT dilatation & function Assess size of pulmonary arteries when repair is being considered Assess interatrial septum
Apical views	Zoom on cardiac crux to establish & measure abnormal septal displacement (>2 cm or >8mm/m²) Assess tricuspid valve anatomy including degree of direct attachment of anterior leaflet into lateral wall of RV Assess functional right ventricular function Assess degree of atrialisation of right ventricle (Celemajer Index) Assess TR severity at origin of jet (large compliant RA may mask hepatic flow reversal) Assess left ventricular function
Suprasternal views	Assess aortic arch SVC flow may show flow reversal in cases of severe TR.

Ebstein Anomaly Reports:

Key points to include in transthoracic echo report:

• Valve anatomy including displacement towards apex and rotation towards the RV outflow tract
• Functional RV size & function. In severe cases, this may be only the RVOT
• Degree of atrialisation of the right ventricle
• Severity of tricuspid regurgitation
• Size of pulmonary arteries
• LV size & systolic function
• Atrial septal integrity

Key views specific to Ebsteins Anomaly:

Figure 3. Apical 4 chamber view demonstrating significant apical displacement of the TV septal leaflet (arrow). A large component of the RV is atrialised. .

Fig ure 2. PLAX: note the abnormal enface orientation of the tricuspid valve. This demonstrates the abnormal anterior rotation of the valve. The RV is also dilated.

Figure 4. Severe TR from 4 chamber view with tricuspid valve Doppler profile. Note the laminar flow of tricuspid regurgitation indicating severe deficiency of valve function. Estimation of pulmonary pressures is not reliable in this scenario.

A B

S

P

A

AoV

B

Figure 5. Carpentier type IV Ebsteins: in the 4 chamber view (A), there are no discernible leaflets due to marked anterior rotation of the valve, only the moderator band is seen. In the 5 chamber view (B), with the aortic valve as a landmark, all 3 leaflets are seen enface.

Supplementary ACHD Echo Acquisition Protocol for

Repaired Tetralogy of Fallot

The following protocol for echo in adult patients with repaired Tetralogy of Fallot (TOF) is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to repaired TOF.

Background

TOF is the most common cyanotic congenital heart disease. Anatomic malformations include:

1. RVOT obstruction, typically subpulmonary infundibular stenosis

2. VSD

3. Overriding aorta

4. RV hypertrophy

Diagram of tetralogy of Fallot. Diagram adapted from Popelova et al

Infundibular stenosis

Aorta overriding the VSD

Common associations

• ASD (~33% of cases) (Tetralogy anatomy + ASD = Pentalogy of Fallot)
• Right aortic arch (25%)
• Coronary artery anomalies (up to 10%). The commonest is when the LAD arises from the RCA & crosses RVOT anteriorly which has important implications for the surgical approach.
• Aortopulmonary or bronchopulmonary collaterals
• 22q11 deletion (15%)
• Persistent left SVC (10%)
• AVSD (2%)

Surgical approaches

Strategies and timing of surgical repair have evolved over time. Currently systemic to pulmonary shunts are no longer performed except in rare cases and total repair is done in the first 3-6 months of life.

• RVOT patch + VSD closure – in setting of adequate pulmonary annulus. Procedure of choice
• Transannular RVOT patch + VSD closure – to increase RVOT/pulmonary annulus size
• RV-PA conduit + VSD closure – most often used in the setting of coronary artery anomalies +/- augmentation of pulmonary arteries.
• BT shunt (classic or modified) is a palliative procedure to encourage growth of pulmonary arteries in neonates. Historically, in rare cases, Waterston shunt (ascending aorta to right pulmonary artery) and Potts shunt (descending aorta to left pulmonary artery) were performed.

Residual anatomic and haemodynamic lesions in repaired TOF

• Residual pulmonary regurgitation
• Residual or recurrent RVOT obstruction and branch PA stenosis
• Akinetic RVOT free wall and RV dilatation and dysfunction
• Restrictive RV
• Residual VSD, ASD
• Tricuspid regurgitation
• Aortic dilatation and regurgitation
• Left ventricular dysfunction
• Conduction and rhythm abnormalities

Imaging protocol for repaired Tetralogy of Fallot

Subcostal views	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapse to assess RA pressure Hepatic venous Doppler to assess for increased A wave reversal velocity Ventricular septum for residual VSDs Anterior angulation to assess anatomy and function of right ventricular outflow RV wall thickness and RV function
Parasternal views	Overall RV function including specifically the anterior wall & outflow tract RVOT anatomy – aneurysmal, narrowing Pulmonary valve annulus diameter, function, degree of PR Doppler of pulmonary valve for gradients & estimation of pulmonary pressures, including presence of forward ‘a’ wave indicating restrictive RV physiology Identify level of stenosis where relevant Anatomy of main pulmonary artery and proximal branches, including branch dimensions. Ventricular septal motion for signs of volume or pressure overload Aortic annulus, root and ascending aorta diameters, degree of AR Integrity of VSD patch Dilatation of coronary sinus
Apical views	Detailed LV function assessment. Assess aortic valve function Detailed RV size and function assessment including fractional area change. Anterior angulation to assess anatomy and function of right ventricular outflow Assess tricuspid valve function Posterior angulation to coronary sinus
Suprasternal views	Assessment of arch sided-ness by demonstrating innominate artery bifurcation. Assessment of branch pulmonary arteries and PR Assessment of right +/- left-sided SVC in the setting of dilated coronary sinus Wide sweeps to assess for aortopulmonary or bronchopulmonary collaterals

Repaired Tetralogy of Fallot Reports

Key points to include in transthoracic echo report:

• RV size, systolic and diastolic function
• Pulmonary valve function
• VSD patch integrity
• Aortic root dilatation
• Estimate of pulmonary pressure
• Assess for PA branch stenosis

Key views specific to ToF repair patients:

Parasternal long axis view

Figure 1 The arrow points to the VSD patch which is brighter than the myocardium. Note that the aortic root still slightly overrides the ventricular septum. The right ventricle is dilated as is commonly seen in adults with repaired ToF, usually associated with pulmonary regurgitation.

Parasternal short axis views

Figure 3 PA bifurcation: Diastolic flow reversal is noted in the pulmonary branches indicating severe PR, a common finding in repaired ToF. The trans-annular patch interrupts the integrity of the pulmonary annulus.

Figure 2 The RVOT is dilated and usually has some akinetic regions following repair using the trans-annular patch technique. The aortic root appears irregular due to the VSD patch. Careful interrogation with CFI is warranted to exclude residual VSDs.

Figure 4 CW Doppler profile of the pulmonary valve: Note the PR ends prematurely in mid diastole due to rapid equalisation of RV & PA pressures. This can indicate severe PR (combined with a wide colour jet).

PW RVOT Doppler

Figure 5. PW Doppler, with Doppler sample at the tip of the pulmonary valve, demonstrates forward flow following atrial systole or a forward ‘a wave’. This suggests RVEDP is markedly elevated, higher than PAEDP which opens the pulmonary valve during atrial systole. It can vary throughout the respiratory cycle. RV restrictive physiology is suggested when the forward a wave is present for 5 consecutive beats during normal respiration. This is often complemented by high velocity atrial reversals in the hepatic veins.

Supplementary ACHD Echo Acquisition Protocol for

TGA – Atrial Switch repair (Mustard/Senning)

The following protocol for echo in adult patients with Transposition of the Great Arteries (TGA) and atrial switch repair is intended as a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to TGA with atrial switch repair.

Atrial Switch Surgical Techniques

Mustard & Senning operations establish appropriate connection between the systemic venous pathways and the subpulmonic ventricle and between the pulmonary venous pathway and the systemic ventricle at the expense of a morphological right ventricle support systemic circulation.

• They share a similar goal which serves to create the following flow patterns:
  • Flow from the IVC & SVC is redirected to the left atrium – left ventricle – pulmonary artery
  • Pulmonary venous flow is redirected to the right atrium –right ventricle – aorta.
• While these two operations differ surgically, the echocardiographic appearance is indistinguishable.

 

1. Mustard procedure B. Senning Procedure

Diagram A. Mustard Procedure: Uses baffles made from Dacron, GoreTex or pericardial tissue to redirect flow B. Senning Procedure: Uses tissue from the right atrium and the atrial septum to redirect flow. Diagrams from Popelova et al

Post-operative Sequelae:

Baffle obstruction

o SVC baffle obstruction more common following Mustard operation

o PV baffle obstruction is more common following Senning operation

Baffle leaks

o Small leaks are common and not haemodynamically important, except in the case of cryptogenic stroke

o Large leaks are rarer but important due to associated volume overload

LV outflow obstruction (33% patients)

o Produces pulmonary stenosis & protects pulmonary arterial bed

o Can be dynamic or fixed

Pulmonary hypertension

o is reported in up to 7% of patients, especially in those with prior VSD and those repaired later in life. Can cause LV dilatation & loss of usual sub-pulmonary LV crescent shape

Systemic RV

o Hypertrophy

o Dilatation (lack of reference values for systemic RV)

o Systolic function invariably deteriorates over time

Tricuspid regurgitation

o The tricuspid valve regurgitation is predominantly due to annular dilatation and is likely functional rather than due to primary organic abnormality. In rare cases, structural tricuspid valve abnormalities also exist.

Imaging protocol for TGA atrial switch

Subcostal view	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapsibility Hepatic venous Doppler to assess for evidence of IVC baffle stenosis Assessment of RV wall thickness & preliminary assessment of size & function Baffle assessment as sometimes well aligned for Doppler
Apical views	Atrial baffles: Pulm veins-RA best seen in ap4 IVC-LA best seen in ap4 with posterior angulation & slight anti-clockwise rotation. Also seen ap2. SVC-RA best seen in ALAX. Can also be seen in ap2. Pacing lead may provide a clue. CFI & PW Doppler looking for phasic forward flow through pathways. In normal situation, baffle velocity <1.0m/sec but phasic flow is the most important feature. CFI to assess for baffle leaks. The CF scale or Nyquist limit might need to be reduced to appreciate small shunt. Agitated saline study may be required to exclude leaks in venous baffle. Atrioventricular connection Including valvular morphological & functional assessment Systemic RV assessment: Size & function assessment for comparison with previous study. Normal reference ranges do not apply. Subpulmonary LV assessment: LV typically small & crescent-shaped with septum bowing towards the LV. A normal sized or dilated LV may indicate pulmonary hypertension or baffle leak with significant left to right shunt. Pulmonary/left ventricular outflow: Assess for obstruction Assess diastolic pressures from pulmonary regurgitation velocity
PLAX/RV inflow	Assess LV size & geometry (should be small & crescent-shaped, compressed by the systemic RV). Demonstrate parallel relationship of the great vessels with aorta anterior Assess pulmonary artery & aortic root size Assess for aortic regurgitation (contributes to systemic RV volume overload) Demonstrate SVC-LA baffle with CFI in long axis view Assess for pulmonary regurgitation
Parasternal short axis	Demonstrate anterior/posterior & left/right relationship of great vessels Assess biventricular function & septal curvature (should be toward LV, if straight/normal may suggest pulmonary hypertension) Demonstrate IVC-LA baffle with CFI Demonstrate pulmonary venous-RA baffle CFI Assess for baffle leak or VSD
Suprasternal views	Assessment of pulmonary branches SVC flow PW Doppler assessment is useful in assessing the SVC-LA baffle if obstructed or may show flow reversal in the setting of significant leak.

TGA Atrial Switch Reports

Key points to include in transthoracic echo report:

• Systemic RV size (serial comparison) and systolic function
• Systemic valve function
• Sub-pulmonary LV size (should be smaller than normal) and systolic function
• Estimate of mean PA pulmonary pressure from PR Doppler
• Baffle patency and any evidence of leaks

Key views specific to atrial switch patients:

Subcostal Views:

Figure 1 Pulmonary Venous pathway: A) The arrow shows the pulmonary venous pathway. B) Red colour flow shows pulmonary venous flow entering into the pulmonary venous atrium (PVA).

Apical 4 Chamber View:

Figure 2 Typical apical 4 chamber view in an atrial switch patient. sRV:systemic right ventricle; pLV: sub-pulmonary left ventricle; LA: morphologic left atrium; PVB: pulmonary venous baffle; PVA: pulmonary venous atrium;

Figure 3 Apical 4 chamber view showing A) pulmonary venous flow into the right atrium & B) IVC flow into the left atrium – slight posterior angulation and anti-clockwise rotation is often helpful for obtaining a longitudinal section of the IVC baffle (IVCB).

Apical 2 Chamber View:

Figure 4 IVC baffle from 2 chamber view, also showing the pulmonary venous atrium in cross-section

Apical Long Axis View:

Figure 5 SVC baffle seen entering the left atrium.

Parasternal View:

Figure 6 A)Small crescent-shaped LV (LV dimension demonstrated by arrow) & B) dilated LV suggestive of LV pressure or volume overload

Figure 7 Variation of LV size with respiration

Figure 8 Parallel relationship of great vessels.

Figure 9 PLAX view of SVC pathway with pacemaker wire (arrow) just posterior from PA

Parasternal Short Axis Views:

Figure 10 A) Anterior/posterior relationship of great vessels. The aorta is anterior and to the right of the pulmonary artery. B) Normal appearance post atrial switch: the high pressures in the systemic RV cause reversed septal curvature and push the ventricular septum towards the left.

Parasternal Short Axis Views:

Figure 11 PSAX views demonstrating A) pulmonary venous baffle, B) IVC-LA baffle

Parasternal Short Axis Views:

Figure 12 Arrows shows IVC baffle leak from PSAX view.

Figure 13 A) Normal respiratory variation noted in hepatic veins. B) Pulsed Doppler from R supraclavicular view of SVC; phasic and returning to baseline, suggesting no obstruction.

Figure 14 Flow profiles in pulmonary venous pathway. Top) Elevated flow velocity in baffle >1.0m/s but flow still returns to baseline suggests mild stenosis. Bottom) continuous flow which never returns to the baseline suggests significant stenosis. The waveform is the most important indicator of obstruction rather than velocity.

Figure 15 A positive bubble study showing a fully opacified sub-pulmonary LV and bubbles crossing into the systemic ventricle. This demonstrates pulmonary -to-systemic circulation shunting suggestive of baffle leak

Supplementary ACHD Echo Acquisition Protocol for

TGA – Arterial Switch repair

The following protocol for echo in adult patients with Transposition of the Great Arteries with arterial switch repair is intended as a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to TGA with arterial switch repair.

Arterial Switch Operation – Surgical Techniques

The arterial switch operation corrects d-transposition circulation and anatomy by connecting the great vessels to their appropriate ventricles. This has been the standard operation for dextro-transposition (d-TGA) since the mid-late 1980’s and is usually performed in the first week of life.

Diagram. Jatene’s arterial switch operation – diagram adapted from Popelová et al

• Jatene’s arterial switch operation involves transection of both great arteries above the semilunar valves and then
  • the aorta (originally arising from the right ventricle) is transferred to its correct position and is connected to the left ventricle. The valve (which was the pulmonary valve) remains in position and is now known as the neo-aortic valve – it functions as an aortic valve but is morphologically a pulmonary valve.
  • the coronary arteries & buttons are explanted from the pulmonary root are reimplanted into the neo-aortic root.
  • the main pulmonary artery is pulled from its posterior position so that it becomes anterior to the aorta (LeCompte manoeuvre). The branch arteries now straddle the aorta, unlike in the normal branch artery anatomy. Not all patients with arterial switch operation have this LeCompte procedure. Reference to the surgical notes of individual patients is recommended.
  • the original aortic valve remains untouched and is now referred to as the neo-pulmonary valve.

Post-operative Sequelae:

• Supravalvular pulmonary artery stenosis, caused by scarring at the anastomosis or origin of the branch arteries, requires re-intervention in about 5–30% of patients
• Supravalvular aortic stenosis occurs less often, with re-intervention required by about 2% of patients
• Right ventricular outflow tract obstruction (RVOTO) develops in the presence of a hypertrophic infundibulum
• Progressive dilatation of the neoaortic root occurs more often in complex TGA (with VSD) which can compress the branch pulmonary arteries
• Various degree of aortic valve regurgitation occurs in up to 50% of patients
• LV systolic dysfunction often seen in patients with coronary artery anomalies

Imaging Protocol for TGA – arterial switch repair

Subcostal view	Establish abdominal and atrial situs, cardiac position & direction of apex
Apical views	Ventricular function Global ventricular function Assessment of regional wall motion abnormalities related to stenosis of re-implanted coronary arteries Assess for myocardial perfusion with contrast Valvular assessment Aortic regurgitation Superior angulation for pulmonary regurgitation or supravalvular stenosis
PLAX views	Routinely measure aortic root assessing for dilatation and supravalvular stenosis Assess for aortic regurgitation & supravalvular narrowing Assess for pulmonary regurgitation Assess for supravalvular pulmonary stenosis including in the main, left and right pulmonary arteries
Parasternal short axis	Use a very high PSAX view to demonstrate the branch pulmonary arteries +/- LeCompte manoeuvre Careful interrogation of stenosis at all anastomosis sites along the pulmonary artery – including left & right branch PAsAssess aortic regurgitation
Suprasternal views	Careful assessment of pulmonary branches – use of alternative windows e.g. supraclavicular views may be helpful Assess for supravalvular aortic stenosis

TGA Arterial Switch Reports

Key points to include in transthoracic echo report:

• RV size & function
• Estimate of RV systolic pressure
• Patency of PA branches, especially when LeCompte performed
• LV size & systolic function
• Aortic valve function
• Aortic root size

Key views specific to arterial switch patients:

Figure 1 High PSAX view demonstrates the LeCompte manoeuvre. The pulmonary artery branches straddle the ascending aorta. This patient has dilated pulmonary arterial branches due to PA hypertension. This view can be difficult to obtain in majority of patients.

Figure 2 Another example of the LeCompte manoeuvre. Note on the 2D image the origin of the RPA is narrowed, resulting in stenosis & turbulent colour flow.

Figure 3 Supravalvular aortic stenosis at the aortic root anastomosis site. The sinotubular junction is measured here.

Figure 4 Dilatation of the neo-aortic root (original pulmonary root) may cause aortic regurgitation.

Supplementary ACHD Echo Acquisition Protocol for

Rastelli repair

The following protocol for echo in adult patients with a Rastelli procedure and is intended as a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to Rastelli repair.

Rastelli Operation – Surgical Technique:

Rastelli operations are performed most commonly in patients with a variety of congenital abnormalities, the common theme being the presence of a ventricular septal defect frequently associated with right ventricular outflow tract obstruction:

• Double outlet right ventricle with a VSD
• Transposition of the great arteries with a VSD
• Truncus arteriosus

Diagram. Rastelli operation

diagram adapted from Popelová et al

The procedure uses a patch to deviate blood from the left ventricle, across the native ventricular septal defect, to the aorta (which in VA discordance remains in its anterior position). The preoperative location of the VSD is important; VSDs which are committed to the great arteries fare better than remotely located VSDs, which are difficult to use in the re-routing of LV outflow.

Where present, the native pulmonary artery is disconnected proximally and a valved right ventricular to pulmonary artery conduit is inserted. The location of the conduit is usually very anteriorly in close proximity to the sternum, which often necessitates the use of non-standard imaging windows to profile with echocardiography.

Post-operative Sequelae:

• LV outflow obstruction
• RV-PA conduit dysfunction
• VSD patch leak
• Aortic root dilatation
• Bi-ventricular dysfunction
• Arrhythmias

Imaging Protocol

Parasternal views

Assess integrity of VSD patch Exclude LVOT gradient -often better alignment than in apical views due to acutely angulated LVOT. Use high parasternal views to assess RV-PA conduit as is an extracardiac conduit – it is usually located very anteriorly and requires non standard views. Aim to interrogate both proximal & distal ends of the conduit as it can narrow at either end. It may be useful to palpate for the thrill associated with the conduit stenosis and to place the transducer at that location. Assess for aortic root dilatation

Apical views

Note serpiginous route of LV outflow, exclude obstruction & assess aortic valve function. Assess integrity of VSD patch Ventricular function in the setting of arrhythmias Obtain RVSP using TR jet. RVSP>2/3 systemic blood pressure suggests significant RVOT obstruction or presence of pulmonary hypertension.

Rastelli Repair Report

Key points to include in transthoracic echo report:

• Clearly state the original anatomy. Rastelli operations can be used for other anatomies as well as dTGA.
• VSD patch integrity
• LV outflow haemodynamics
• Aortic root size
• RV-PA conduit haemodynamics & assess for regurgitation
• Estimate of RV systolic pressure

Key views specific to Rastelli Repair:

Parasternal views:

AoV

VSD patch

VSD

Figure 1 The aorta remains in its anterior position and the LV outflow is through the VSD. The LVOT becomes elongated and sometimes acutely angulated. It is important to identify LVOT obstruction using colour and Doppler.

VSD

Figure 2 A residual VSD patch leak. The patch re-routes the flow from the LV to the anterior aorta, and so can be quite long.

Figure 3 RV-PA conduit: this is usually positioned right underneath the sternum and requires very high parasternal views. The conduit is long and can narrow at either end, hence assessing the length of the conduit is important and may require multiple views as seen here.

Apical views:

Figure 4 The elongated LVOT has increased musculature at the VSD site which causes LV outflow obstruction.

Supplementary Echo Acquisition Protocol for

Congenitally Corrected Transposition of the Great Arteries

The following protocol for echo in adult congenital heart patients with congenitally corrected transposition of the great arteries (ccTGA) is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to ccTGA patients.

Background

Congenitally or “physiologically corrected” transposition of the great arteries is a congenital heart condition characterized by discordant atrioventricular and ventriculo-arterial connections. It is also known as double discordance, levo-TGA and cc-TGA. It is a very uncommon congenital heart defect (0.5% of congenital heart defects). The RV is the subaortic ventricle supporting the systemic circulation and the LV is the subpulmonary ventricle supporting the pulmonary circulation. The systemic AV valve is the morphologically tricuspid valve.

Diagram. ccTGA: discordant atrioventricular and ventriculo-arterial connections

Diagram from Popelova et al

Common associations

VSD

Tricuspid valve (systemic AV valve) abnormalities e.g. Ebstein-like malformation

Tricuspid regurgitation

Aortic regurgitation

Systemic right ventricular dysfunction

Subvalvular pulmonary stenosis

Malalignment of the atrial septum and inlet part of the IVS in usual arragement in the atria (reversed crux).

Heart block

Mesocardia, dextrocardia.

Imaging protocol for cc-TGA

View	Area of interest
Subcostal view	Establish abdominal and atrial situs, cardiac position & direction of apex Assess IVC size & collapse to assess RA pressure Systemic RV function assessment (visual) Systemic RV wall thickness assessment Tricuspid valve morphology, mechanism and severity of TR Retrograde flow abdominal aorta (in cases where > moderate AR present)
Parasternal views	In ccTGA, initial images can be confusing. No standardized parasternal long axis views are possible Use short axis views to establish the spatial relationship of aorta and pulmonary artery. The aorta is typically anterior and leftward of the pulmonary artery. Use multiple nonconventional planes to visualize additional defects, valve morphology and function
Apical views	Detailed systemic RV size and function assessment. RV is identified by moderator band, apical displacement and septal attachments of it’s AV valve. Assess LV size and function (usually crescent-shaped/compressed by systemic RV) Atrioventricular connection RV: Assessment of tricuspid valve morphology, inflow and regurgitation Pulmonary vein Doppler when regurgitation is moderate to severe Atrioventricular connection LV: assess mitral regurgitation CW mitral regurgitation for LV systolic pressure (representing pulmonary systolic pressure only when pulmonary stenosis is absent) Ventriculo-arterial connection (normally aorta is positioned leftward and anterior to the PA however, there is a wide variability in the spatial relationship between the great vessels) Apical 5 chamber view superior tilting for LV- LVOT- PA connection Apical 5 chamber view extensive superior tilting for RV-RVOT-Ao connection Pulmonary/LV outflow: assess for gradient (sub-valvular and valvular) assess pressures from pulmonary regurgitation velocity Aorta/RVOT: assessment of aortic valve function assessment aortic regurgitation LA and RA size
Suprasternal views	Retrograde diastolic flow in descending aorta

ccTGA Reports

Key points to include in transthoracic echo report:

• Systemic RV size (serial comparison) and systolic function
• Systemic tricuspid valve anatomy and function
• Aortic valve function
• Sub pulmonary ventricular size & function
• Sub pulmonary outflow anatomy, especially for subvalvular pulmonary stenosis.

Key views for ccTGA

Figure 1: Apical 4 chamber view – for assessment of the cardiac crux & ventricular morphology. (Left) AV discordance, (right) zoomed in view of the cardiac crux showing reversed offset

LV

RV

Figure 2: PSAX view. (left) side by side orientation commonly seen in ccTGA, (right) both great arteries are seen in short axis, with the aorta anterior and to the left of the pulmonary artery

Figure 3: Ebstein-like tricuspid valve seen in ccTGA

Echocardiographic Assessment of Fontan/TCPC repairs

The following protocol for echo in adult patients following Fontan or TCPC procedure is intended as a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included where valid. It highlights areas of interest in each view specific to Fontan or TCPC evaluation.

Background:

The terms ‘Fontan Operation’ & ‘Total Cavopulmonary Connection’ (‘TCPC’) indicate a concept of circulatory flow rather than a specific type of operation. There are several surgical techniques used to achieve the same outcome.

The main aim of the Fontan circulation is to separate pulmonary & systemic circulations by removing the systemic venous return & its deoxygenated blood from the heart. A single ventricle (or functional single ventricle) often pumps both the systemic and pulmonary circulations. In many cases, the native anatomy also involved a single ventricle physiology.

In Fontan physiology:

• IVC flow is channelled directly to the pulmonary artery and so the circulation bypasses the sub-pulmonary ventricular pump which is small and rudimentary in many cases.
• Multiple step operations are required usually consisting of a Glenn followed by completion of the TCPC.

Bidirectional Glenn operation:

• the SVC is disconnected from the right atrium and redirected into the right pulmonary artery, which remains confluent, hence flow is bidirectional – to both left and right pulmonary arteries.
• Where a left SVC persists, a left-sided SVC-LPA anastomosis can be performed, so creating a bilateral bidirectional Glenn.
• A Glenn operation is not always associated with a complete TCPC. It is sometimes used in isolation e.g.. repair of Ebstein’s anomaly to improve flow to the pulmonary arteries and to unload a small right ventricle. This is also known as a one-and-a-half ventricular repair.

Diagram 1. Bidirectional Glenn operation with confluence of the pulmonary arteries. Diagram from Popelová et al. Congenital Heart Disease in Adults, 2008.

Fontan or TCPC – Are they the same?

Diagram 2 a) An atriopulmonary Fontan, b) Lateral tunnel TCPC, c) extracardiac TCPC. Diagram from Marc R. de Leval & John E. Deanfield Nature Reviews Cardiology 7, 520-527 (September 2010)

1. Atriopulmonary (AP) Fontan

An AP Fontan operation usually describes a direct AP connection by opening the right atrial appendage directly into the main pulmonary artery with no artificial tubes/patches. If a tricuspid valve or atrial septal defect was present, they were both patched closed, and the main pulmonary artery was disconnected often about 1cm above the pulmonary valve. It is sometimes performed with a Glenn operation or, the SVC is left to drain normally into the right atrium. The AP Fontan operation is no longer performed in infants due to its undesirable long term effects of right atrial distension leading to arrhythmias, thrombus & pulmonary venous obstruction.

Post operative sequelae specific to AP Fontan:

• Right atrial dilatation leading to arrhythmias and/or thrombus formation
• Pulmonary venous obstruction
• Narrowing of anastomosis site.

2. Lateral tunnel TCPC

A lateral tunnel TCPC refers to a tunnel (Gore-Tex/Dacron) inserted into the right atrium which directs blood from the inferior vena cava through the right atrium and into the right pulmonary artery. It allows the right atrioventricular valve to contribute to the systemic circulation. In the apical 4 chamber view, a circular structure is noted in the right atrium. A bidirectional Glenn is performed to carry SVC flow directly to the right pulmonary artery. Fenestration in the systemic atrium is performed at the time of operation if the pulmonary vascular resistance is borderline high. The fenestration allows for offloading of increased pressure within the conduit and is vital to keep the Fontan circulation functional. The gradient of the fenestration represents the difference between pulmonary artery & right atrial pressure (i.e. the transpulmonary gradient, which is determined by the PVR) and should usually be 5-8mmHg. Fenestrations are sometimes closed with septal occluder devices later in life if they cause ongoing cyanosis.

Post operative sequelae specific to lateral tunnel TCPC:

• Narrowing of conduit
• Thrombus in conduit
• Spontaneous closure of fenestration if present

3. Extracardiac TCPC

An extracardiac TCPC is a conduit which, like a lateral tunnel, directs blood from the inferior vena cava into the right pulmonary artery, however it is not within the atrial cavity, and so allows both the right atrium and right atrioventricular valve to contribute towards the systemic circulation. It is the current approach and it is hoped that it will reduce the incidence of atrial arrhythmias. A bidirectional Glenn is also performed. The extracardiac approach allows for better streamlining of blood flow from the IVC directly superiorly to the right pulmonary artery.

Indication of Fontan/TCPC:

• Any pathology where either ventricular chamber is hypoplastic & unlikely to successfully support either a pulmonary or systemic circulation on its own. This includes, but is not restricted to, tricuspid or mitral atresia.
• Any pathology where atrioventricular valve chordae straddle the septum, preventing VSD closure and therefore also preventing biventricular repair. This includes, but is not restricted to, double inlet ventricles, AVSDs.

Post-operative Sequelae common to all surgical techniques

• Ventricular dysfunction, systolic and diastolic.
• Complications with conduits – narrowing, obstruction, leaks, thrombus formation
• Atrioventricular valve and /or aortic valve regurgitation which increases systemic ventricular volume loading and pulmonary (Fontan) pressures.
• Restrictive VSD in patient with tricuspid atresia or double inlet LV with VA discordance. Haemodynamic effect of restrictive VSD is similar to that of sub-aortic stenosis.

Imaging protocol for Fontan/TCPC repair

Imaging Window	Assessment particular to Fontan/TCPC
Subcostal view	Assess situs, cardiac position and direction of apex Assess hepatic veins for dilatation and IVC collapse (2D & Doppler) Assess TCPC patency by following IVC flow Assess SVC drainage (in AP Fontan) Exclude RA or conduit thrombus
Apical views	Establish AV and VA connection Ventricular function assessment Assess AV & aortic valve function Exclude restrictive ASD or VSD where applicable Diastolic function assessment –ventricular inflow and pulmonary venous inflow, for serial comparison Exclude pulmonary venous compression Assess TCPC patency, fenestration size & mean gradient Exclude intracardiac or intraconduit thrombus
Parasternal views	Assess ventricular size where possible for serial comparison Assess ventricular morphology Establish VA connection Exclude restrictive VSD Exclude thrombus Valvular assessment Assess pulmonary arteries in SAX views Assess atriopulmonary connection and TCPC patency when possible, including PW Doppler to identify respiratory variation of blood flow.
Suprasternal views (including supraclavicular views).	Assess Glenn patency Assess TCPC patency at pulmonary artery end where possible, using PW Doppler to identify respiratory variation. Exclude pulmonary branch stenosis and coarctation Assess for aorto-pulmonary collateral flow

Single ventricle reports:

Key points to include in transthoracic echo report:

• A clear description of anatomy is required using the sequential segmental analysis
• Ventricular function
• Valvular function
• Any obstruction – across septal defects, valves, vessels or conduits
• Patency of connections
• Thrombus
• Fenestration gradient if present

Assessment of single ventricular function:

• Conventional parameters for assessment of either left or right ventricular function are not applicable due to the unique geometry of the single ventricle +/- contribution of the

rudimentary chamber.

• In situations where the single ventricle is a morphological left ventricle and maintains its basic shape, e.g. tricuspid atresia, Simpson’s biplane EF can still be useful.
• Outside of visual estimation, fractional area change may be the most reliable method for serial assessment as it makes no geometric assumptions.
• Other methods which do not rely on geometry may be useful:
  • Myocardial performance index
  • Isovolumic acceleration time
  • Systolic to diastolic (S:D) ratio from AV valve Doppler

Assessment of Connections:

The normal Doppler profile of flow in a Glenn or TCPC depends on the type of surgery performed. The general principles for both connections are the same. Optimisation of colour flow scales (low Nyquist limit) & spectral Doppler (scale & low velocity filter settings) is strongly recommended.

Figure 1 Normal Glenn flow in AP Fontan:

Note that after the p wave, flow reversal is noted in the Glenn connection, due to a transient rise in right atrial pressure resulting from contraction of the right atrium. Flow is low velocity and phasic, returning to the baseline with every cardiac cycle.

Figure 2 Effect of the respiratory cycle:

It should be noted that Fontan circulations are driven by both the cardiac cycle and the respiratory cycle. Respiratory variation in flow in the connections is considered as a helpful adjunct to help the circulation. During inspiration, the negative pressure is created in the intrathoracic cavity, which helps to ‘suck’ blood into the pulmonary circulation.

Figure 3 Conduit stenosis:

In this example, there is a continuous gradient between

the non-pulsatile superior vena cava and the right atrium. This

suggests a degree of partial obstruction. Complete obstruction

will result in no forward flow.

 

5 important considerations for comprehensive echocardiographic assessment

of patients following Fontan/TCPC operations

1. Know & understand the original anatomy
   • The group of patients selected for TCPC is heterogeneous. Knowing if holes should be open or closed, if they are unimportant or vital, can make life-saving differences to theinterpretation of the examination.
2. Read the surgical notes
   • There are 3 main operations which are seen in adult patients, but beware that variations are common.
   • It is important to know which connections have been made (e.g. Björk procedure or RA to RV Fontan).
   • And beware of the 3^rd connection (most likely in the setting of a persistent left SVC).
3. Understanding normal relationships helps to find connections
   • To find the conduits requires an excellent command of 3-dimensional spatial orientation and echo acoustic windows. Think in terms of anterior or posterior rather than sticking to conventional echo views.
4. Know how to drive the echo machine
   • Especially colour Doppler scale, gains & spectral Doppler low velocity filters
   • Fontan flow is low and slow. Default machine settings will nearly always fail to see the venous flow.
5. Serial evaluation is the best assessment

• Due to the heterogeneity of the group, the patient is their own best control. Sometimes the changes can be subtle but important. Compare ventricular function, diastolic parameters and valvular regurgitation using side-by-side images from the current and previous exams.

Key views specific to Fontan/TCPC repairs:

To view the proximal end of the IVC connection:

Figure 4 Subcostal short axis view of the IVC end of the conduit. Follow the flow from the IVC as it courses superiorly away from the abdomen (blue flow). Note the significant reduction of colour scale makes the flow easier to follow.

Imaging RA connections in AP Fontan:

Figure 5 Subcostal 4 chamber view with superior angulation. The connection is seen with blue flow travelling away from the right atrium – the AP connection is frequently in close proximity to the usual SVC-RA junction (red flow, not seen in this image).

Imaging the Glenn Connection:

Figure 6 Images of the SVC from the right supraclavicular view. Left) SVC flow is noted travelling inferiorly towards the junction of the Glenn connection with the right pulmonary artery. Right) red colour flow from the distal end of the TCPC is noted flowing superiorly towards the right pulmonary artery [this view not always obtainable]. Note the significant reduction of colour scale makes the flow easier to follow.

Supplementary Echo Acquisition Protocol for

Pulmonary Hypertension associated with

Adult Congenital Heart Disease (PH-ACHD)

The following protocol for echo in adult congenital heart disease patients with pulmonary hypertension is a guide for performing a comprehensive assessment of this group of patients. It is intended as a supplementary guide to the ISACHD echo protocol and sequential analysis and all regular measurements should be included. It highlights areas of interest in each view specific to pulmonary hypertension.

Background

Pulmonary hypertension (PH) is a haemodynamic and pathophysiological condition defined as an increase in mean pulmonary arterial pressure (mPAP) ≥25 mmHg at rest as assessed by right heart catheterization. PH can be found in multiple clinical conditions. Due to fundamental difference in treatment strategy, it is critical to differentiate pulmonary arterial hypertension (PAH) from pulmonary hypertension due to left heart disease. The former has been defined as mPAP ≥25 and pulmonary arterial wedge pressure (PAWP) ≤ 15 mmHg and a pulmonary vascular resistance >3 Wood units.

Clinical classification

Pulmonary arterial hypertension associated with adult congenital heart disease represents a very heterogeneous population. According to recent guidelines¹, patients can be classified

into the following four major groups:

1) Eisenmenger syndrome.

Includes all large intra- and extra-cardiac defects which begin as systemic-to-pulmonary shunts and progress with time to severe elevation of pulmonary vascular resistance (PVR) and to reversal (pulmonary-to-systemic) or bidirectional shunting; cyanosis, secondary erythrocytosis, and multiple organ involvement are usually present.

2) PAH associated with large systemic-to-pulmonary shunts.

Includes moderate to large defects; PVR is mildly to moderately increased, systemic-to-pulmonary shunting is still prevalent, whereas cyanosis at rest is not a feature. Some of these patients may still benefit from surgical or interventional partial or complete closure of the defect.

3) PAH with small/coincidental defects.

Marked elevation in PVR in the presence of small cardiac defects (usually ventricular septal defects <1 cm and atrial septal defects <2 cm of effective diameter assessed by echo), which themselves do not account for the development of elevated PVR; the clinical picture is very similar to idiopathic PAH. Closing the defects is contra-indicated.

4) PAH after defect correction.

Congenital heart disease is repaired, but PAH either persists immediately after correction or recurs/develops months or years after correction in the absence of significant postoperative haemodynamic lesions.

In addition, there are patients with unilateral or segmental pulmonary arterial hypertension and pulmonary hypertension due to systemic ventricular disease including patients with systemic right ventricle (CCTGA, TGA post atrial switch repair).

Role of Echocardiography

Transthoracic echocardiography is the first-line imaging modality in pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD). Echocardiography provides detailed structural and hemodynamic assessment allowing the detection of previously undiagnosed congenital heart defects as well as infer a diagnosis of pulmonary hypertension (table 1 and 2)². It is also very helpful in differentiating PAH from PH due to left heart disease (figure 1)³. During follow-up of patients with known PH, transthoracic echocardiography is used to image the effects of PH on the heart and to monitor the change in PAP.

Imaging protocol for PH in ACHD

View	Areas of interest	PAH specific measurements
Parasternal views	Overall RV size & function including the anterior wall & outflow tract M-mode for septal motion only Doppler of pulmonary valve Degree of pulmonary regurgitation & estimation of PA mean & end-diastolic pressure Anatomy of main pulmonary artery and proximal branches Tricuspid regurgitation velocity for RV systolic pressure Presence of pericardial effusion Assess for shunt lesions	LV size & wall thickness RV dimension (PLAX) Main PA dimension PR early Vmax PR end Vmax PV Vmax PV Acceleration time PV ejection time PV VTI TR velocity RV and LV end systolic dimension ratio – figure 2 LV eccentricity index
Apical views	Detailed LV systolic function assessment Detailed LV diastolic function assessment Detailed RV size and function assessment (qualitative [compared to LV size] & quantitative). Ensure RV focussed view is used for RV dimensions RA size Tricuspid valve assessment Assess for shunt lesions	LV basal dimension RV basal, mid, length dimensions RA area RA volume LA volume MV & TV E velocity MV & TV A velocity TV inflow duration– figure 3 TR velocity TR duration LV lateral M-mode – MAPSE LV septal M-mode – Septal APSE RV lateral M-mode – TAPSE LV lateral S’, E’, A’ velocity LV medial S’, E’, A’ velocity RV lateral S’, E’, A’ velocity
Subcostal views	Assess IVC size & collapse to assess RA pressure Hepatic venous Doppler to assess for increased A wave or flow reversal Pericardial effusion	IVC dimension at end expiration
Suprasternal views	Assessment of branch pulmonary arteries

Table 1: Echocardiographic probability of pulmonary hypertension in

symptomatic patients with a suspicion of pulmonary hypertension

Peak TR velocity* (m/s)	Presence of other echo PH signs	Echo probability of PH
≤2.8 or not measurable	No	Low
≤2.8 or not measurable	Yes	Intermediate
2.9-3.4	No
2.9-3.4	Yes	High
>3.4	Not required

*Peak TR velocity is valid in the absence of pulmonary outflow obstruction. Table adapted from Galie N. et al: 2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension. European Heart Journal (2015) 37, 67–119

Table 2: Echocardiographic signs suggesting pulmonary hypertension used to assess the probability of pulmonary hypertension in additions to tricuspid regurgitation velocity measurement.

A: The ventricles	B: Pulmonary artery	C: Inferior vena cava & right atrium
RV/LV basal diameter ratio >1.0	RV outflow Doppler acceleration time < 105ms &/or midsystolic notching	IVC dimension >21mm with decreased inspiratory collapse (<50% with a sniff or <20% with quiet inspiration)
Flattening of the IVS (LV eccentricity index >1.1 in systole &/or diastole)	Early diastolic PR velocity > 2.2m/s	RA area (end-systole) > 18cm2
	PA dimension > 25mm
*Echocardiographic signs from at least different categories (A/B/C) from the list should be present to later the level of echocardiographic probability of pulmonary hypertension

Adapted from Galie N. et al: 2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension. European Heart Journal (2016) 37, 67–119

PH in ACHD reports

Key points to include in transthoracic echo report:

• Estimate of pulmonary pressure using TR velocity & pulmonary Doppler
• RV size & function
• Septal motion
• Hepatic vein status
• Any contributing valve disease
• LV diastolic function assessment is crucial and may determine management strategy

Figure 1: Examples of typical pre- and postcapillary PH:

Adapted from D’Alto M et al. Echocardiographic Prediction of Pre- versus Postcapillary Pulmonary Hypertension J. Am Soc Echo 2015, 28: 108-15 and Jone PN et al, Right Ventricular to Left Ventricular Diameter Ratio at End-Systole in Evaluating Outcomes in Children with Pulmonary Hypertension J. Am Soc Echo Feb 2014;27)

Figure 2: Parasternal short axis view of LV and RV.

RV and LV end-systolic dimensions. Adapted from Jone PN et al, JASE Feb 2014;27

Figure 3 : Continuous wave Doppler recording of tricuspid valve regurgitation:

S = TR duration, d = TV inflow duration. As described in Moceri P el al. Circulation 2012;126:1461-1468 & Alkon J. Am J Cardiol 2010;106:430-436)

References/further reading

1. Galie N. et al: 2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension. European Heart Journal (2016) 37, 67–119

2. D’Alto M et al. Echocardiographic Prediction of Pre- versus Postcapillary Pulmonary Hypertension J. Am Soc Echo 2015, 28: 108-15

3. Jone PN et al, Right Ventricular to Left Ventricular Diameter Ratio at End-Systole in Evaluating Outcomes in Children with Pulmonary Hypertension J. Am Soc Echo Feb 2014;27

4. Moceri P el al. Echocardiographic Predictors of Outcome in Eisenmenger Syndrome Circulation 2012;126:1461-1468

5. Alkon J, Hupl T, Manlhiot C, et al. Usefulness of the right ventricular systolic to diastolic duration ratio to predict functional capacity and survival in children with pulmonary arterial hypertension. Am J Cardiol. 2010;106:430–436.