Prognostic value of right ventricular diastolic function indices in hypertrophic cardiomyopathy

Abstract

Despite the fact that the role of left ventricular diastolic dysfunction in hypertrophic cardiomyopathy (HCM) patients' prognosis has been established, the effect of increased right ventricular (RV) diastolic filling pressures still remains unclear. The purpose of this study was to determine the prognostic significance of transthoracic echocardiographic indices of RV diastolic function (tricuspid inflow and tricuspid annulus tissue Doppler imaging) in HCM patients. We followed up 386 patients diagnosed with HCM (aged 49.3 ± 17.2 years; 65% male) for a median period of 67 months (interquartile range 26-189 months). Primary endpoints were considered mortality due to heart failure (HF) (13 patients) and total cardiovascular (TC) mortality [HF, sudden cardiac death and its equivalents (35 patients)]. Patients presenting with an increased RV E/E(r) ratio (ratio of tricuspid in flow E wave to E(r) wave obtained by tissue Doppler imaging at the lateral tricuspid annulus) had a 1.6 times greater risk for HF mortality [hazard ratio (HR): 1.6, 95% confidence interval (CI): 1.1-2.4, P = 0.03] while patients with shortened tricuspid E wave deceleration time (DTE) had a 1.1 greater risk for SCD (HR: 1.1, 95% CI: 1.01-1.2, P = 0.03). Following ROC analysis, the optimal RV indices' cut-off values for the recognition of our study endpoints were assessed [E/E(r) = 6.88, sensitivity 75%, specificity 77.4%, area under curve (AUC) 0.847, P = 0.017 for HF mortality and DTE < 239 ms, sensitivity 62.5%, specificity 56.7%, AUC 0.642, P = 0.05 for TC mortality]. The establishment of RV restrictive physiology appears to have significant predictive value in HCM, regardless of the presence of other detrimental risk factors.