[Exercise tolerance for indicating of aortocoronary bypass surgery (author's transl)].

In order to evaluate effects of aortocoronary bypass grafting on exercise tolerance, we analyzed the data of 109 patients who performed exercise tests before and one month or one year after surgery. Subgroups of patients were formed on the basis of preoperative exercise tolerance. Previously severely impaired patients benefited from surgery by an improvement of exercise capacity, whether preoperative left ventricular enddiastolic pressure at rest exceeded 16 mm Hg and left ventricular ejection fraction was below 50% or not. On the other hand, exercise capacity of patients who were comparable in respect to the numbers of coronary lesions and bypass grafts but whose exercise tolerance was less impaired preoperatively did not improve after surgery. Because in such patients, independent of coronary anatomy, surgery has been reported to be ineffective for prolongation of life, indication for aortocoronary bypass grafting in the presence of "good" exercise capacity must be questioned for symptomatic as well as for prognostic reasons.