Right ventricular performance in essential hypertension

Abstract

Effects of systemic hypertension on right ventricular (RV) performance have not been previously investigated. In this study, 10 normal patients were compared to 20 patients with uncomplicated, asymptomatic essential hypertension (defined as cuff diastolic blood pressure > 100 mm Hg) after a complete hemodynamic and RV cineangiographic evaluation. The mean intra-arterial pressure in the normal group was 93 ± 11 vs 120 ± 13 mm Hg in the essential hypertension group (p <0.01). All right-sided pressures were substantially higher in the hypertensive than in the normal patients (mean right atrial pressure: 2 ± 1 mm Hg for normals, 5 ± 3 mm Hg for hypertensives, p <0.01; RV end-diastolic pressure: 3 ± 2 mm Hg for normals, 5 ± 2 mm Hg for hypertensives, p <0.05; mean pulmonary artery pressure: 12 ± 3 mm Hg for normals, 17 ± 5 mm Hg for hypertensives, p <0.01; mean pulmonary capillary wedge pressure: 6 ± 1 mm Hg for normals, 9 ± 3 mm Hg for hypertensives, p <0.01. Cardiac index in normal and hypertensive patients was nearly identical (2.93 ± 0.80 l/min/m2 in normals, 3.11 ± 0.67 l/min/m2 in hypertensives, NS). In contrast, a markedly lower cineangiographic RV ejection fraction was present in the hypertensive compared with the normal patients (68 ± 6% vs 59 ± 7%, p <0.01). The lower RV ejection fraction was due to the proportionately greater increase in the RV end-systolic volume index (22 ± 5 ml/m2 for normals, 34 ± 8 ml/m2 for hypertensives, p <0.01) than in the end-diastolic colume index (69 ± 13 ml/m2 for normals, 82 ± 16 ml/m2 for hypertensives, p <0.04) in the hypertensive patients. It is concluded that 1) hypertensive patients have higher right-sided pressures than normals, and 2) RV performance in essential hypertension may be characterized by a lower RV ejection fraction than in normal subjects.