Preoperative evaluation of cardiac failure and ischemia in elderly patients by cardiopulmonary exercise testing.

Major surgery in the elderly continues to have a high mortality rate. Preoperative myocardial ischemia is a known risk factor. Cardiac failure is also a risk factor, but is difficult to quantify objectively. One hundred eighty-seven elderly surgical patients were evaluated for cardiac failure by cardiopulmonary exercise testing (CPX). The overall mortality in these patients was 7.5 percent. If three deaths secondary to surgical causes are excluded, mortality was 5.9 percent. There were 55 patients in whom the anaerobic threshold (AT) was less than 11 ml/min/kg; of these, 10 died, a mortality rate of 18 percent. There were 132 patients with an AT of greater than 11 ml/min/kg and of these, 1 patient died, giving a mortality rate of 0.8 percent (p < 0.001). A low AT associated with preoperative ischemia resulted in the death of 8 of 19 patients, a mortality rate of 42 percent. When the ischemia was associated with the higher AT, then 1 patient out of 25 died, a mortality rate of 4 percent (p < 0.01). Both preoperative ischemia and preoperative cardiac failure are independent risk factors for perioperative mortality in the elderly.