Predicting survival after coronary revascularization for ischemic cardiomyopathy

Area of Science:

• Cardiology
• Cardiac Surgery
• Vascular Biology

Background:

• Coronary revascularization for ischemic cardiomyopathy (ejection fraction ≤ 0.25) has unpredictable success rates.
• Hospital operative mortality for these procedures is surprisingly low, especially with evidence of ischemia.
• Liberalized selection criteria were based on the hypothesis that coronary artery bypass grafting (CABG) is safe in this subset, irrespective of distal coronary vasculature status.

Purpose of the Study:

• To examine the hypothesis that CABG is safe for patients with low ejection fractions.
• To identify predictors of poor outcome in patients with ejection fractions of 0.25 or lower undergoing CABG.
• To determine if distal coronary vasculature status influences surgical outcomes in this patient population.

Main Methods:

• Retrospective study of 96 patients with ejection fractions ≤ 0.25 undergoing CABG between 1983 and 1993.
• Exclusion criteria included valvular heart disease, ventricular aneurysm resection, or emergency operations.
• Catheterization films were reviewed by a blinded cardiovascular surgeon to assess vessel quality (good, fair, poor).

Main Results:

• The overall hospital mortality rate was 8% (88 survivors).
• Increased age and poor vessel quality were the only significant predictors of poor outcome.
• Sex, angina status, ejection fraction, arrhythmia, cross-clamp time, and graft number did not significantly affect perioperative outcomes.

Conclusions:

• Poor distal coronary vasculature and older age predict poor outcomes in patients with low ejection fractions undergoing myocardial revascularization.
• Poor distal coronary vasculature is a contraindication for CABG in patients with an ejection fraction of 0.25 or less, even with angina.
• These findings refine patient selection criteria for CABG in severe ischemic cardiomyopathy.