Does the additive risk of mitral valve repair in patients with ischemic cardiomyopathy prohibit surgical intervention?

OBJECTIVE To assess the surgical risk of additional mitral valve repairs in patients with ischemic cardiomyopathy. SUMMARY BACKGROUND DATA Severe mitral regurgitation in patients with ischemic cardiomyopathy increases the death rate and symptomatic status. The 1-year survival rate for medical therapy in this subset of patients is less than 20%. Transplantation is usually not feasible because of donor shortage and death while on the waiting list. METHODS To assess additive risk, a retrospective chart review from 1993 to 1998 was performed comparing patients with ischemic cardiomyopathy (ejection fraction [EF] <25%) and severe mitral regurgitation undergoing mitral valve repair and coronary artery bypass graft operations with patients with an EF of <25% undergoing coronary artery bypass graft alone. These groups were also compared with 140 patients receiving heart transplants since 1993 (group 3). RESULTS The overall hospital death rate for group 1 was 6.3%. The one death occurred 2 weeks after surgery secondary to sepsis. This was not significantly different from the death rate of 4.1% in group 2. In group 1, there were two deaths at 1 year (87% survival rate), one related to heart failure. One patient was New York Heart Association (NYHA) class IV at 1 year; the remainder of patients were NYHA class I-II. These results were not significantly different than the 8% death rate noted with transplantation. There was no change in EF and minimal residual mitral regurgitation in group 1 based on postoperative transesophageal echocardiography, whereas group 2 had an average 11.7% improvement in EF. CONCLUSIONS Previously, severe mitral regurgitation in the setting of ischemic cardiomyopathy has been associated with poor survival. In these authors' experience, repairing the mitral valve along with coronary artery bypass grafting does not increase the surgical risk, yields improvement in symptomatic status, and compares favorably to coronary artery bypass grafting alone and cardiac transplantation. However, the lack of change in EF in these patients probably represents an overestimation of the EF before surgery secondary to severe mitral regurgitation.