Coronary Artery Bypass Graft Surgery in Patients with Ischemic Cardiomyopathy and Severe Left Ventricular Dysfunction: Short and Long-Term Results

Abstract

Background: We evaluated the prognostic value of pre-operative parameters, surgical risk, functional benefits and long-term survival after myocardial revascularization in patients with established ischemic cardiomyopathy.

Methods: Seventy-one patients with ischemic cardiomyopathy, severe left ventricular dysfunction (left ventricular ejection fraction < 30%), and myocardial perfusion evaluated by Thallium-201 scintigraphy, were studied before and after myocardial revascularization, during hospitalization and throughout 48 months (average) of late follow-up.

Results: The early postoperative mortality was 2.8% and the five-year survival rate was 62.8%. When the survival rate was studied, there was no correlation with 1) the presence of Q-waves on preoperative cardiogram, 2) the presence of ischemia on Tl-201 scintigraphy, 3) the degree of left ventricular ejection fraction, or 4) the presence of angina. There was a statistically significant difference for survivors and non-survivors in the following parameters: 1) functional class IV of CHF, and 2) the presence of left bundle-branch block (LBBB).

Conclusions: Our surgical results confirm that myocardial revascularization is a safe procedure, and that it increases late survival and improves the quality of life in patients with ischemic cardiomyopathy and severe left ventricular dysfunction. We also observed that due to hete rogeneous coronary and myocardial patterns of ischemic cardiomyopathy, preoperative prognostic parameters are difficult to establish. Preoperative functional class IV congestive heart failure, and LBBB were the main predictors of poor outcome following surgical revascularization for ischemic cardiomyopathy.