Failure to improve left ventricular function after coronary revascularization for ischemic cardiomyopathy is not associated with worse outcome

Abstract

Background - Preoperative identification of viable myocardium in patients with ischemic cardiomyopathy is considered important because CABG can result in recovery of left ventricular (LV) function. However, the hypothesis that lack of improvement of LV function after CABG is associated with poorer patient outcome is untested. Methods and Results - Outcome was compared in patients with ischemic LV dysfunction (LVEF ≤0.30) with and without improvement in LVEF after CABG. Of 135 consecutive patients, 128 (95%) survived CABG and 104 (77%) had preand post-CABG LVEF assessment. Of these 104 patients, 68 (65%) had >0.05 increase in LVEF (group A) and 36 (35%) had no significant change, or ≤0.05 decrease in LVEF (group B) compared with pre-CABG LVEF. No significant differences existed in age, gender, comorbidities, baseline symptoms, baseline LVEF, or intraoperative variables between groups A and B. Group A increased LVEF from 0.24±0.05 to 0.39±0.1 (P<0.005). In Group B, LVEF did not change significantly postoperatively, 0.24±0.05 to 0.23±0 06 (P=NS). Postoperative improvement in angina and heart failure scores were similar between the 2 groups. Survival free of cardiac death was similar for both groups (93% in group A and 94% in group B, P=NS) at a mean follow-up of 32±23 months. Conclusions - Lack of improvement of global LVEF after CABG is not associated with poorer outcome compared with that of patients with improved LVEF, presumably because effective revascularization of ischemic myocardium, even without improvement in ventricular function, protects against future infarction and death.