Right ventricular function in severe non-ischaemic mitral insufficiency

Mitral insufficiency (regurgitation) is a disease of both ventricles. To determine the pathophysiological implications and clinical value of assessment of right ventricular function in this disease, right ventricular ejection fraction was determined by radionuclide cineangiography (r = 0.73, P less than 0.01, vs contrast angiography, n = 30) in patients with severe, non-ischaemic mitral regurgitation. Among 31 patients with isolated mitral regurgitation treated medically, five died, all within 2 years of follow-up; all five were among the eight patients with left ventricular ejection fraction less than or equal to 45% (lower limit of normal), and among the six patients with right ventricular ejection fraction less than or equal to 30% (almost invariably associated with at least mild pulmonary hypertension). During the same period, valve replacement was performed in 22 patients with isolated mitral regurgitation; among the six patients with right ventricular ejection fraction less than or equal to 30% before operation, only one died (P less than 0.05), indicating the risk-mitigating effect of valve replacement. Among eight pre-operative patients with combined mitral and aortic regurgitation, four died within 7 years after double valve replacement; all patients with right ventricular ejection fraction during exercise less than 20% died. After mitral valve replacement for isolated mitral regurgitation, right ventricular ejection fraction improved rapidly (average 8% in less than 1 year (P less than 0.05); 3% more at 3 years after operation (P less than 0.05)). Post-operative symptom persistence was predictable from ventricular ejection fraction before operation less than 30% (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)