Survival after myocardial revascularization for ischemic cardiomyopathy: A prospective ten-year follow-up study

Abstract

Objective: The aim was to prospectively analyze all-cause mortality, predictors of survival, and late functional results after myocardial revascularization for ischemic cardiomyopathy over a 10-year follow-up. Methods: We prospectively studied 57 patients with stable coronary artery disease and poor left ventricular ejection function (<35%), enrolled between 1989 and 1994. Stress thallium was analyzed in 37 patients to identify reversible ischemia. To avoid patients with a stunned myocardium, we excluded those with unstable angina or myocardial infarction within the previous 4 weeks. Mean age of the patients was 67 ± 8 years, and 93% of patients were men. Mean left ventricular ejection fraction was 0.28 ± 0.04, 50% were in Canadian Cardiovascular Society angina class III-IV, and 65% were in New York Heart Association functional class III-IV. Results: Operative mortality was 1.7% (1/57). The mean left ventricular ejection fraction (0.30) at 15 months postoperatively did not change from before operation (0.28, P = .09). There were 8 deaths at 1 year and 42 deaths over the course of the study, producing a survival of 82.5% at 1 year, 55.7% at 5 years, and 23.9% at 10 years (95% confidence interval: 14.6%-39.1%). Symptom-free survival was 77.2% at 1 year and 20.3% at 10 years. The leading cause of death was heart failure in 29% (12/42). Multivariate analysis showed that large reversible defects on stress thallium were associated with improved left ventricular ejection fraction at 1 year (P = .01) but only male sex was associated with improved long-term survival (P = .036). Conclusions: Myocardial revascularization for ischemic cardiomyopathy is associated with good functional relief from the symptoms of angina initially and, to a lesser extent, heart failure. Revascularization may have the advantage of preserving the remaining left ventricular function. However, the long-term mortality remains high.