The value of preoperative exercise testing in predicting long-term survival in patients undergoing aortocoronary bypass surgery.

To determine whether preoperative exercise testing adds important independent prognostic information in patients undergoing coronary bypass surgery, 35 variables were analyzed in 1241 patients enrolled in the Coronary Artery Surgery Study registry. All patients underwent a treadmill exercise test before bypass surgery and were followed for up to 7 years. Survival in this surgical cohort was 90.6% (1124 of 1241). Multivariate stepwise dicriminant analysis identified the left ventricular score and the final exercise stage achieved as the two most important (p less than .001) independent predictors of postoperative survival. In a subgroup of 416 patients with three-vessel coronary disease and preserved left ventricular function, the probability of postoperative survival at 7 years ranged from 95% for those patients able to exercise to stage 4 to 83% for those whose ability was limited to stage 1 of exercise. Thus, the preoperative exercise test, by assessing the functional capacity of the cardiovascular system, is an important independent predictor of postoperative survival.