Survival predictors in patients with a left ventricular ejection fraction of 10-30% receiving a coronary bypass: analysis of preoperative variables.

A total of 224 patients with angina pectoris and a left ventricular ejection fraction in the range of 10-30% (mean 24.2%) underwent coronary artery bypass grafting between April 1986 and August 1991. These patients received a mean (s.d.) of 2.9 (0.3) aortocoronary vein grafts. The overall operative mortality rate was 8.9%. The 1-, 2- and 3-year survival rates were 87.7%, 86.7% and 85.2%, respectively. Analysis of operative risk factors showed that patients with an end-diastolic left ventricular pressure > 24 mmHg were significantly more at risk (mortality rate 20.0%, P < 0.05) than those with an end-diastolic left ventricular pressure < or = 24 mmHg (mortality rate 6.2%). Patients with a perioperative cardiac index < 2.5 l min-1m-2 had higher mortality (25.4%) than those with a cardiac index > or = 2.5 l min-1m-2 (mortality 1.9%, P < 0.001). The operative mortality rate of patients with a cardiac index < 2.5 l min-1m-2 and an end-diastolic left ventricular pressure > 24 mmHg was 40.5%. Patients with a left ventricular ejection fraction of 10-20% were not significantly more at risk (P > 0.05) than those with a left ventricular ejection fraction of 21-30%.