Coronary artery surgery study (CASS): a randomized trial of coronary bypass surgery. Eight years follow-up and survival in patients with reduced ejection fraction

Abstract

Survival data after 8 years of follow-up for all patients and after 7 years for certain subgroups are reported from CASS, a randomized trial of surgical or medical treatment assignment in patients with coronary artery disease who have less than severe angina or are asymptomatic after myocardial infarction. After 8 years, survival curves are not significantly different between medical and surgical groups; 87% of patients assigned to surgical and 84% of those assigned to medical treatment are alive. A significant advantage favoring surgical assignment was observed in patients with three-vessel disease and reduced ejection fractions (less than 0.5. but greater than 0.35); after 7 years of follow-up, 88% of the patients in the surgical group and 65% of those in the medical group are alive (p = .009). Survival curves for patients with normal resting ejection fractions are identical after 7 years. We conclude that the CASS trial reveals a significant advantage favoring surgical therapy in patients with three-vessel disease and impaired ventricular function who are randomly assigned to treatment.