Surgery in severe rheumatic mitral valve disease--recognition of severity and risk factors.

The postoperative course of 294 patients with rheumatic mitral valve disease, who underwent mitral valve surgery during a period from July, 1978 to June, 1981, was studied by comparing the influences of the following clinical parameters: a low left ventricular ejection fraction (LVEF), a high pulmonary arterial systolic pressure (PASP), a high pulmonary vascular resistance (PVR), tricuspid regurgitation (TR), a high right ventricular end-diastolic pressure (RVEDP) and a giant left atrium (GLA). The patients with a functional capacity of class III or IV according to the New York Heart Association were classified into 3 groups (improved, unimproved and died), and from this data we calculated the improvement ratio and the mortality rate. The improvement ratios were 73% in patients with a low LVEF, 70% with a high PASP, 78% with a high PVR, 66% with TR, 11% with a high RVEDP and 77% with a GLA; the mortality rates were 19, 14, 17, 24, 78 and 19%, respectively. As compared with the case of deteriorated left ventricular performance and pulmonary hypertension, deteriorated right ventricular performance, especially high RVEDP, was accompanied by a comparatively poorer surgical prognosis. It is concluded that mitral valve surgery should be performed during the period in which the right ventricular function is still preserved.