[Surgical indications in mitral valve stenosis, combined mitral valve defect or mitral valve insufficiency. Long-term prognosis of operated or drug-treated patients].

Data obtained from 683 patients with mitral valve disease, NYHA-class III or IV, were retrospectively studied by means of a multivariate Cox regression analysis. Based on symptoms and hemodynamic findings, surgical intervention had been recommended for all patients: closed mitral commissurotomy (n = 361), prosthetic mitral valve replacement (n = 241) and prosthetic mitral valve replacement together with a corrective procedure for the tricuspid valve (n = 81). While the majority of patients underwent surgery during the observation period (n = 528), a substantial number of patients continued on medical treatment (n = 155). The mean observation periods were 52, 49 and 31 months, respectively, in the three collectives. Surgically treated patients in whom closed mitral commissurotomy had been recommended had a better prognosis (p less than 0.0003) than those treated medically (five-year survival rate 89% vs. 63%). Age, clinical severity, previous mitral commissurotomy, pulmonary vascular resistance and right atrial mean pressure had no significant influence on prognosis. In patients in whom prosthetic mitral valve replacement had been recommended, surgical treatment led only to tendencial improvement in prognosis as compared with those treated medically (five-year survival rate 78% vs. 61%). Factors with an unfavorable influence on prognosis were age more than 49 years (p less than 0.05), pure mitral regurgitation (p less than 0.001), NYHA-class IV (p less than 0.02) and right atrial mean pressure in excess of 4 mm Hg (p less than 0.01). In patients in whom prosthetic mitral valve replacement together with a corrective procedure for the tricuspid valve had been considered necessary, surgical treatment had no significant influence on prognosis as compared with those treated medically (five-year survival rate 57% vs. 53%). Patients in whom previous mitral commissurotomy had been performed had an extremely poor prognosis (p less than 0.001). Pulmonary vascular resistance was significantly reduced both after mitral commissurotomy as well as after prosthetic mitral valve replacement; this was associated with a significant decrease in right atrial mean pressure and increase in right ventricular ejection fraction. The indication for closed mitral commissurotomy, thus, appears established in patients with symptoms of class III or IV clinical severity. The indication can be established generously since the surgical mortality is low and long-term prognosis is good.(ABSTRACT TRUNCATED AT 400 WORDS)