Long-term outcome of isolated coronary artery bypass surgery in patients with severe left ventricular dysfunction

Area of Science:

• Cardiology
• Cardiac Surgery
• Clinical Outcomes Research

Background:

• Coronary artery bypass grafting (CABG) is a standard treatment for coronary artery disease.
• Patients with severely impaired left ventricular function (LVF) historically have a poor prognosis.
• Contemporary outcomes for CABG in high-risk LVF patients require updated estimates.

Purpose of the Study:

• To assess the contemporary prognosis of patients with severely reduced left ventricular function undergoing CABG.
• To compare outcomes of CABG in patients with low, moderate, and normal ejection fractions (EF).

Main Methods:

• Analysis of the APPROACH registry data from 1996-2001 in Alberta, Canada.
• Comparison of isolated CABG outcomes in 7841 patients categorized by EF: Lo EF (<30%), Med EF (30-50%), and Nl EF (>50%).
• Statistical analysis including operative mortality, 5-year survival, and adjusted hazard ratios.

Main Results:

• Operative mortality was higher in Lo EF (4.6%) vs. Med EF (3.4%) and Nl EF (1.9%) groups (P<0.001).
• Five-year survival was 77.7% for Lo EF, 85.5% for Med EF, and 91.2% for Nl EF patients (P<0.001).
• Adjusted hazard ratio for death in Lo EF vs. Nl EF was 1.98; 1-year mortality was lower for CABG vs. non-revascularized Lo EF patients (OR 0.36).

Conclusions:

• CABG can be performed with acceptable perioperative mortality in patients with severely reduced left ventricular function.
• Contemporary 5-year survival for this high-risk group is improved compared to historical data.
• CABG is a viable option for selected patients with impaired LVF, offering survival benefits over non-revascularization.