We analyzed surgical results of 91 patients who underwent re-mitral valve replacement (reMVR) for valve morbidity between January 1981 and March 1994 in an attempt to draw some therapeutic guidelines. The study population consisted of 38 men and 53 women, ages 32-73 (mean 52 +/- 10) years. The causes of valve morbidity were structural deterioration in 71 patients, nonstructural dysfunction manifested by paravalvular leakage in 5 valve thrombosis in 7 and prosthetic valve endocarditis in 8. Twelve of ninety-one patients (13.2%) died postoperatively in the hospital. All the patients were divided into the survivors (n = 12) and the nonsurvivors (n = 79). Mean right atrial pressure, extracorporeal circulation time, concomitant coronary artery bypass grafting, and application of intra-aortic balloon pumping were significantly different between the groups. Twenty preoperative and intraoperative variables were analyzed by means of univariate and multivariate analysis. By univariate analysis, male gender, NYHA IV, history of congestive heart failure, renal insufficiency and prosthetic valve stenosis were related to a higher incidence of hospital death. Multivariate analysis revealed that male gender and NYHA IV were risk factors in reMVR, and indicated no differences in intraoperative parameters between survivors and deaths. It is recommended to examine patients with bioprostheses thoroughly and to perform early elective reMVR before a patient develops NYHA IV.