Right ventricular-pulmonary arterial uncoupling in mild-to-moderate systemic hypertension

Mild-to-moderate hypertension with preserved left ventricular (LV) function may be associated with right ventricular (RV) dysfunction and increased pulmonary vascular resistance (PVR).

The present study explored the adequacy of RV-pulmonary arterial (PA) coupling in 211 never-treated hypertensive patients (mean blood pressure, BP 112 ± 12 mmHg) and 246 controls (BP 93 ± 12 mmHg). They underwent a comprehensive transthoracic Doppler echocardiography, and RV-PA coupling was estimated by the tricuspid annular plane systolic excursion (TAPSE) to systolic pulmonary artery pressure (PASP) ratio (TAPSE/PASP).

Compared with the controls, hypertensive patients had increased LV wall thickness and decreased trans-mitral E/A with only slight but significant increase in transmitral Doppler E wave to tissue Doppler mitral annulus e' wave ratio (6.3 ± 1.9 vs. 5.8 ± 1. 5, P < 0.05). RV dimensions and indices of either systolic or diastolic function were not different. PASP was increased in the hypertensive patients (25 ± 7 vs. 21 ± 7 mmHg, P < 0.001), as was PVR estimated from the tricuspid regurgitation velocity to right ventricular outflow tract velocity ratio (1.7 ± 0.4 vs. 1.5 ± 0.5 Wood units, P < 0.001). The TAPSE/PASP ratio was decreased (1.08 ± 0.35 vs. 1.43 ± 0.67 mm/mmHg, P < 0.001). This difference was mainly driven by male hypertensive patients. At multivariable analysis, the only independent predictors of decreased TAPSE/PASP were age and blood pressure.

The TAPSE/PASP is markedly decreased in hypertension without heart failure, chiefly in men, with only slight increases in estimates of LV filling pressure or PVR, suggesting RV-PA uncoupling.