Coronary bypass surgery in chronic stable angina.

Over the last 20 years, operative mortality has decreased and late survival has improved for patients with chronic stable angina who have coronary artery bypass surgery. However, this favorable trend may not continue because the operation is now extended to elderly and high-risk patients. The most powerful predictors of operative mortality include indexes of left ventricular function, age, and the number of associated medical conditions. Female gender, severity of angina, and extent of coronary artery disease appear to be predictors of operative mortality in some series but not in all. Indexes of left ventricular dysfunction remain the most powerful predictors of late death, but the extent of coronary disease, older age, and presence of associated diseases (including noncardiac vascular disease) remain important determinants. Analyses of the randomized trials and registry studies reveal a consistent trend: in patients at high risk on the basis of clinical, functional, and anatomic characteristics, coronary artery bypass surgery prolongs survival in comparison with medical therapy alone. In patients determined to be at low risk, medical therapy is initially recommended with the realization that revascularization may be necessary subsequently if symptoms worsen or the severity of ischemia increases.