Right ventricular strain differences between idiopathic and systemic sclerosis Pulmonary Hypertension

Abstract

Background: Right ventricular (RV) contractility has been shown to be significantly worse in systemic sclerosis-associated pulmonary arterial hypertension (SSPAH) versus idiopathic PAH (IPAH), despite similar afterloads. Speckle-based strain may be a useful tool in conjunction with conventional 2D echocardiography (2DE) for detection of regional and global RV dysfunction between groups. Aim: To determine differences in conventional and novel measures of RV function between IPAH and SSPAH. Methods: 55 well-characterized PAH patients (23 IPAH, 32 SSPAH) underwent right heart catheterization (RHC) within 5 hours of 2DE. 2DE analysis included tricuspid annular plane systolic excursion (TAPSE) and fractional area change (FAC), as well as novel basal, mid, apical and global RV longitudinal systolic strain (RVLSS). Results: SSPAH patients were more commonly female and older. There were no significant differences in hemodynamic parameters by RHC, or 2D based TAPSE or FAC between SSPAH and IPAH. In contrast, RVLSS was significantly diminished in SSPAH both globally (-12.6 ± 5.1 vs -15.6 ± 4.3%, p=0.03), and regionally, mostly due to a decreased basal RVLSS in SSPAH (-15.5 ± 7.9 vs -24.8 ± 8%, p=0.02). There was no correlation between abnormalities in RVLSS and invasive measures of mean pulmonary arterial pressure, and pulmonary vascular resistance. Conclusion: Under similar afterload, conventional 2DE measures of RV function were not different between SSPAH and IPAH, while speckle-based strain revealed differences in global RV contractility mostly due to decrease in basal RVLSS in SSPAH. These findings are suggestive of unique pattern of RV contractility in SSPAH not detected by 2DE alone.