Adult Congenital Heart Disease

Impact of Right Ventricular Pressure Load After Repair of Tetralogy of Fallot. Latus H, Stammermann J, Voges I, Waschulzik B, Gutberlet M, Diller GP, Schranz D, Ewert P, Beerbaum P, Kühne T, Sarikouch S; German Competence Network for Congenital Heart Defects Investigators *.J Am Heart Assoc. 2022 Apr 5;11(7):e022694. doi: 10.1161/JAHA.121.022694. Epub 2022 Mar 18.PMID: 35301850   Commentary from Dr. Thomas Zellers (Dallas, USA), section editor of Congenital Heart Disease Interventions and ACHD Journal Watch: Introduction and summary: The aim of the study was to assess the hemodynamic impact and prognostic relevance of RV pressure load in a population of patients following tetralogy of Fallot repair. Patients were older than 8 years of age at the time of evaluation with a CMR, echo and exercise stress test. There was no evaluation with initial post-operative RVOT gradient nor was there longitudinal hemodynamic evaluation. There was follow up information on adverse events (ventricular tachycardia or death) and pulmonary valve replacement. Below is the study population algorithm:     Results: Two hundred and ninety-six patients had complete data. Peak RVOT gradients were positively correlated with a) smaller RV volumes b) less pulmonary regurgitation c) lower RV and LV longitudinal systolic strain by echo and d) lower early diastolic strain rates by echo. A trend toward reduced exercise capacity was also found. Using univariable Cox regression analysis, the authors looked at prognostic relevance of RVOT gradients on the primary endpoints of death (n=6), sustained VT (n=2) and non-sustained VT (n=11). Higher RVOT gradients were significantly associated with these combined primary endpoints. Other predictors are shown in Table 2 below. Further, a RVOT peak gradient > 25 mmHg was associated with a > 3-fold increase in adverse cardiovascular events (HR 3.69, P=0.005) as seen in Figure 3. A second univariable Cox proportional hazard analysis that considered only death or sustained VT as showed a significant relationship with those two endpoints. A comparison between patients with RVOT peak gradients < 25     mmHg vs > 25 mmHg, revealed a much higher risk for these two endpoints in patients with higher gradients (HR 17.9, p= 0.007). A separate subgroup analysis looking at peak gradient and degree of PR was conducted. Peak gradients > 25 mmHg and moderate PR (not severe PR) also had a significant increase in combined adverse events. Bivariable testing was then performed to determine a relationship between peak RVOT gradients and the other parameters found to be significantly associated with primary outcome metrics on univariable analysis. These are outlined below in Table 3.     The authors also looked at an association between RVOT gradient and pulmonary valve replacement (PVR). This analysis was conducted in 292 of the 296 eligible patients. Pulmonary valve replacement was performed in 119 (41%) of the patients at a median of 3 years (0.1-12.3 yrs) after CMR evaluation. Using univariable Cox regression analysis, higher RVOT gradients were associated with a need for PVR. Other significant factors include type of palliation (valve sparing vs transannular patch), NYHA class > 1, increased RV volumes and mass, severity of PR and lower RVEF and LVEF. The authors further assessed the effects of mild (< 15 mmHg), moderate (15-30 mmHg) and severe (> 30 mmHg) RVOT gradients and degrees of PR (< 25% and > 25%) on the need for PVR. Patients with < 25% PR and RVOT gradients < 30 mmHg had the lowest risk for PVR (Figure 4 below).   Limitations: Overall, this is an interesting study that looks at the effect of peak gradient and pulmonary regurgitation on endpoints of death, non-sustained VT and sustained VT as well as need for pulmonary valve replacement and provides some insight into risk factors. However, there was no longitudinal and long term follow up from the surgical procedure with regard to these variables.        

Incidence, Risk Factors, and Outcomes of Atrial Arrhythmias in Adult Patients With Atrioventricular Septal Defect. Jacquemart E, Bessière F, Combes N, Ladouceur M, Iserin L, Gardey K, Henaine R, Dulac A, Cohen S, Belli E, Jannot AS, Chevalier P, Ly R, Clavier S, Legendre A, Petit J, Maltret A, Di Filippo S, Hascoët S, Marijon E, Waldmann V.JACC Clin Electrophysiol. 2022 Mar;8(3):331-340. doi: 10.1016/j.jacep.2021.09.004. Epub 2021 Oct 27.PMID: 35331427   Take Home Points Retrospective analysis of 391 patients diagnosed with AVSD (61% women) from 3 French centres (2001-2020). 22% of the cohort had trisomy 21. (Table 1) 85% of the cohort had undergone reparative surgery. A relatively small proportion (n=58, 15%) of the cohort were born with a complete AVSD (100% repaired). Mean age at enrolment 36.3 ± 16.3 years and mean duration of follow up 17 years after surgical repair. One quarter of patients (n=98) developed at least 1 atrial arrhythmia at a mean age of 39 years old. Lifetime risks for developing atrial arrhythmia to ages 20, 40, 60 years were 3.7%, 17.8% and 55.3 respectively. The commonest arrhythmia until the age of 45 years was IART/Focal atrial tachyarrhythmia. At beyond 45 years old, AF was the commonest arrhythmia. Independent risks associated with developing atrial arrhythmias were age; number of cardiac operations; left or right atrial dilation and moderate or severe left AV valve regurgitation (Figure 1). Those patients experiencing atrial arrhythmias had a higher subsequent risk of needing a pacemaker (42% vs 9%; P<0.001) ; developing heart failure (25% vs 1%; P<0.001) and experiencing a stroke (11% vs 3%; P=0.007). Commentary by Dr. Damien Cullington (Liverpool, UK), section editor of ACHD Journal Watch: Patients born with an AVSD are commonly seen in the ACHD clinic – AVSD comprises 7% of all congenital cardiac lesions. Most patients fare well following their surgical repair but there are a number of important issues for the team to watch for over time – mostly these relate to monitoring of valvar regurgitation and possibly stenosis (usually the left valve) and the surveillance of/treatment of atrial arrhythmias or progressive AV block. This analysis is welcomed to help guide and inform the ACHD team and their patients about what chronic risk is posed by atrial arrhythmias to patients with AVSD – mostly those whom have undergone surgical repair. The characteristics of the study cohort are seen in Table 1. It is not documented what antiarrhythmic therapies patients were receiving during their follow up and if this may have adjusted outcomes.   Table 1   Atrial arrhythmias Over a mean FU of 17.3 ± 14.2 years after first surgical repair, one quarter of patients (n=98) presented with at least one episode of atrial arrhythmia (Figure 1). Until the age of 45 years, IART/FAT was the commonest arrhythmia. After the age of 45 years old, AF was commoner. At the end of follow up, approximately three quarters of patients (n=75, 77%) with a history of experiencing atrial arrhythmias subsequently had persistent or permanent atrial arrhythmia. Table 2 shows risk factors for developing atrial arrhythmia. The prevalence of atrial arrhythmia in different phenotypic subgroups is shown in Figure 2.   Table 2 – Risk factors for development of atrial arrhythmias   Figure 1   Figure 2     Limitations It is unclear from the data presented how many patients underwent ablation for atrial arrhythmias during follow up and how this modified their outcomes. It is unclear from the data presented what medical treatments patients received and how this may have modified outcomes. Conclusions Atrial arrhythmias occur frequently in patients with AVSD with over half experiencing such phenomena by the age of 60 years old. Whilst it is important to understand risks for developing atrial arrhythmias, further research is needed to understand how they could be optimally prevented. It would be insightful to understand how medical therapy (i.e. antiarrhythmics) and upfront ablative intervention helps to modify long term outcomes.