Risk stratification for exercise training in cardiac patients: do the proposed guidelines work?

Four authoritative organizations (American Association of Cardiovascular and Pulmonary Rehabilitation [AACVPR], the American College of Cardiology [ACC], the American College of Physicians [ACP], and the American Heart Association [AHA]) have risk stratification guidelines for supervised exercise in patients with cardiovascular disease. The ability of the guidelines to predict exercise complications is untested.

A prospective sample was evaluated that included 239 patients enrolled for a total of 5720 patient exercise hours in a phase II supervised outpatient cardiac rehabilitation exercise program between December 1, 1992, and June 16, 1995, who had had preprogram stress testing and/or left ventricular ejection fraction determination. Complications during supervised exercise were measured.

Overall, 12 patients experienced complications during supervised exercise. None of the guidelines was predictive of complications (positive predictive values, 3-7%). Regression analyses demonstrated that current cigarette smoking was the only predictor of complications. There was reasonable correlation of patient risk stratification among the four guidelines (r = 0.19-0.47; P < 0.0001).

Currently proposed exercise risk stratification guidelines are not predictive of complications during supervised exercise. Further work is needed before exercise risk stratification guidelines are used to adjudicate use of supervised services.