Prevalence and Prognostic Implications of Right Ventricular Dysfunction in Patients With Hypertrophic Cardiomyopathy

Abstract

Right ventricular (RV) dysfunction is a well-known prognostic factor in several cardiac diseases. However, the prevalence of RV dysfunction in hypertrophic cardiomyopathy (HC) is unclear and its prognostic value is unknown. This study aims at addressing these issues assessing RV function with speckle tracking echocardiography. In 267 HC patients (52 ± 15 years, 68% male), standard and advanced echocardiographic measurements of RV function were performed including RV 4-chamber longitudinal strain (RV4CLS) and RV free wall longitudinal strain (RVFWLS). The primary end point was all-cause mortality and heart failure development. RV dysfunction was observed in 9% of patients based on tricuspid annular plane systolic excursion (≤17 mm), 5% based on fractional area change (<35%), 23% based on RVFWLS ≥-19%, 39% based on RVFWLS ≥-23%, and 55% based on RV4CLS ≥-20%. In total 59 (22%) patients reached the primary end point during a median follow-up of 6.7 (interquartile range 4.2 to 9.8) years. Kaplan-Meier survival curve showed a significant worse survival free of the end point for patients with impaired RV4CLS ≥-20% versus patients with preserved RV4CLS <-20% (log-rank 7.0, p = 0.008) and for patients with impaired RVFWLS ≥-19% versus patients with preserved RVFWLS <-19% (log-rank 4.4, p = 0.037). Multivariable Cox regression analysis showed that E/E' (hazards ratio [HR] 2.26 [1.30 to 3.92], p = 0.004), left ventricular global longitudinal strain LV GLS (HR 1.08 (1.01 to 1.17), p = 0.034) and RV4CLS (HR 1.08 (1.02 to 1.15), p = 0.007) were independently associated with the primary end point. In conclusion, RV dysfunction as measured by longitudinal strain is relatively frequent in HC patients. Impaired RV4CLS is - together with LV GLS and E/E' - associated with adverse outcome, which may indicate a more severe form of HC.