MITRAL-VALVE REPAIR IN CARDIOMYOPATHY

Background-Volume overload secondary to mitral regurgitation (MR) in c ardiomyopathy is considered critical in the pathogenesis of subsequent ventricular dysfunction. Open mitral valve repair (OMVP) is hypothesi zed to improve symptomatology and ventricular function by reducing the volume overload of the left ventricle. Methods and Results - All pati ents who underwent OMVP with a left ventricular ejection fraction (EF) of <0.30 (n = 81) from 1984 through 1997 were reviewed (1 patient was lost to follow-up). Fifteen operations (18.5%) were repeat operations after previous coronary artery bypass graft surgery. Preoperative and postoperative EFs and NYHA class were compared. Survival probabilitie s were calculated, and multivariate analysis was performed. The averag e age of all patients was 67.1 years (range, 41 to 83 years). Mean fol low-up was 1.7 years (range, 2 months to 8.5 years). The most common m itral repair was ring annuloplasty. Sixty-two patients (77%) had conco mitant coronary artery bypass graft surgery. The surgery mortality rat e was 11% (9 of 81); 6 of these 9 patients were >70 years old. The ove rall Kaplan-Meier survival probability rate at, 2, 3, 4, and 5 years w as 0.73, 0.68, 0.58, 0.50, and 0.38, respectively. EF improved signifi cantly (0.24 to 0.32; P<0.0001), as did the NYHA class (3.2 to 1.6; P< 0.0001), at follow-up. There was no difference in late survival betwee n patients with an EF of <0.20 (21 patients) and those with an EF betw een 0.20 and 0.30 (P = NS). Risk factors for death included heart fail ure and old age. Conclusions-OMVP for MR in the setting of ischemic ca rdiomyopathy and low EF appear to improve ventricular function, medium -term patient symptomatology, and survival.