Right ventricular remodeling, its correlates, and its clinical impact in hypertrophic cardiomyopathy.

Abstract

Structural right ventricular (RV) abnormalities are present in a substantial proportion of patients with hypertrophic cardiomyopathy (HCM), but the trigger for RV hypertrophy remains unclear. The aim of this study was to assess the relationship between RV and left ventricular (LV) remodeling and the impact of biventricular involvement on clinical status in this setting. Ninety-nine patients with HCM and 30 normal subjects with a similar age and gender distribution were prospectively enrolled. Comprehensive echocardiography was performed in all, including the assessment of LV and RV function by tissue Doppler and speckle-tracking echocardiography. Measurement of RV free wall thickness (RVWT) was performed at end-diastole, in a zoomed subcostal view, focusing on the RV midwall. Patients with HCM had increased RVWT (6.4±1.9 vs 3.6±0.8mm, P<.001) and lower values of RV global longitudinal strain (-19.4±4.4% vs -23.8±2.7%, P<.001) compared with control subjects. RVWT was independently related to LV mass and LV global longitudinal strain. Increased RVWT was correlated with New York Heart Association class (r=0.20, P=.04) and calculated sudden cardiac death risk score (r=0.52, P<.001) and was independently related to the presence of ventricular arrhythmias (odds ratio, 2.02; 95% CI, 1.28-3.19; P=.002). In patients with HCM, the presence of RV hypertrophy was associated with increased LV mass and reduced LV longitudinal strain, correlated with increased calculated sudden cardiac death risk score, and independently related to the presence of ventricular arrhythmias. These data suggest more severe disease in patients with biventricular HCM.