Echocardiographic assessment of right ventricular contractile reserve in patients with pulmonary hypertension

Abstract

Introduction and aim: Right ventricular function is a major determinant of prognosis in pulmonary hypertension. The aim of this study was to assess and compare right ventricular contractile reserve in healthy subjects (controls) and in subjects with pulmonary hypertension (cases).

Methods: In this prospective study of seven cases and seven controls undergoing treadmill stress echocardiography, right ventricular S-wave velocity, tricuspid annular plane systolic excursion (TAPSE), right ventricular fractional area change (RVFAC) and stroke volume index were assessed at rest and with exercise. The increase in each parameter between rest and exercise for cases and controls was analyzed and the magnitude of change in each parameter with exercise between cases and controls was compared.

Results: A significant increase in S-wave velocity was observed in cases (rest: 9.4 ± 3.1; exercise: 13.7 ± 4.8 cm/s [p < 0.05]). In controls there was a statistically significant increase in S-wave velocity (12.9 ± 2.3 to 23.0 ± 7.2 cm/s [p < 0.005]), TAPSE (25.7 ± 2.4 to 31.0 ± 3.5 mm [p < 0.05]) and RVFAC (53.8 ± 14.7% to 64.4 ± 9.9% [p < 0.005]). The magnitude of change in S-wave velocity (cases: 4.3 ± 3.3; controls: 10.1 ± 5.5 cm/s [p < 0.05]), TAPSE (cases: 0.6 ± 2.5; controls: 5.3 ± 3.8 mm [p < 0.05]) and RVFAC (cases: -0.4 ± 11.8; controls: 10.6 ± 5.9% [p < 0.05]) was significantly different between cases and controls.

Conclusions: S-wave velocity, TAPSE and RVFAC increased significantly with exercise in controls. S-wave velocity was the only parameter that showed a significant increase in cases, although the magnitude of this increase was significantly less than in controls.

Keywords: Contractile reserve; Ecocardiografia de esforço; Exercise echocardiography; Hipertensão pulmonar; Pulmonary hypertension; Reserva contrátil; Right ventricle; Ventrículo direito.