Theres L, Hübscher A, Stangl K, Dreger H, Knebel F, Brand A, Hewing B.Cardiovasc Ultrasound. 2020 May 14;18(1):13. doi: 10.1186/s12947-020-00197-z.PMID: 32410698 Free
Background: We aimed to evaluate associations of right atrial (RA) and right ventricular (RV) strain parameters assessed by 2D speckle tracking echocardiography (2D STE) with invasively measured hemodynamic parameters in patients with and without pulmonary hypertension (PH).
Methods: In this study, we analyzed 78 all-comer patients undergoing invasive hemodynamic assessment by left and right heart catheterization. Standard transthoracic echocardiographic assessment was performed under the same hemodynamic conditions. RA and RV longitudinal strain parameters were analyzed using 2D STE. PH was defined as invasively obtained mean pulmonary arterial pressure (mPAP) ≥25 mmHg at rest and was further divided into pre-capillary PH (pulmonary capillary wedge pressure [PCWP] ≤ 15 mmHg), post-capillary PH (PCWP > 15 mmHg) and combined PH (PCWP > 15 mmHg and difference between diastolic PAP and PCWP of ≥7 mmHg). Correlation analyses between variables were calculated with Pearson’s or Spearman’s correlation coefficient as applicable.
Results: Out of 78 patients, 45 presented with PH. Within the PH group, 39 had post-capillary, five had combined pre- and post-capillary PH, and one had pre-capillary PH. Patients with PH had a significantly increased RA area (PH 22.0 ± 9.2 cm2, non-PH 17.3 ± 10.7 cm2; p = 0.003) and end-systolic RV area (PH 14.7 ± 6.1, non-PH 11.9 ± 4.8 cm2; p = 0.022). RV mid strain was significantly reduced in PH (PH -17.4 ± 7.8, non-PH: – 21.6 ± 5.5; p = 0.019). Average peak systolic RA strain (RAS) and average peak systolic RV strain (RVS) showed a significant association with mPAP (r = – 0.470, p = 0.001 and r = 0.490, p = 0.001, respectively) and with PCWP (r = – 0.296, p = 0.048 and r = 0.365, p = 0.015, respectively) in patients with PH. Furthermore, RV apical, mid and basal strain as well as RV free wall strain showed moderate associations with mPAP. In patients without PH, there were no associations detectable between RA or RV strain parameters and mPAP and PCWP.
Conclusion: In an all-comer cohort, RA and RV strain parameters showed significant associations with invasively assessed mPAP and PCWP in patients with predominantly post-capillary PH. These associations may be useful in clinical practice to assess the impact of post-capillary PH on myocardial right heart function.
Fig. 1 Representative example of speckle tracking echocardiography (2D STE-) derived longitudinal strain of the right atrium obtained in the apical 4-chamber view. Dotted white curve indicates mean of all segments. The maximum excursion of the average strain curve  symbolizes the maximum longitudinal strain and RA reservoir function (RAS). RA conduit function was calculated from the difference between RAS and the end of the conduit phase in early diastole  and RA contractile function was derived from the difference between the endpoint of conduit phase and the peak RA contraction 
Fig. 2 Representative example of speckle tracking echocardiography (2D STE-) derived longitudinal strain of the right ventricle obtained in the apical 4-chamber view. Dotted white curve indicates mean of all segments, where RVS is derived from maximum excursion. The RV Free wall consists of three segments, which are colored red, dark blue and pink in the STE analysis