Coronary artery surgery study (CASS): a randomized trial of coronary artery bypass surgery. Quality of life in patients randomly assigned to treatment groups.

To evaluate the comparative effects of medical and surgical therapy on quality of life of patients with stable ischemic heart disease, 780 patients who had been randomly assigned to medical or surgical therapy in the CASS were systematically followed for a mean of 5.5. years. Analysis was performed according to original treatment assignment. Patients in the surgical group had significantly less chest pain, fewer activity limitations, and required less therapy with nitrates and beta-blockers. Treadmill exercise tests performed 6, 18, and 60 months after entry documented significantly longer treadmill time, less exercise-induced angina, and less ST segment depression among surgical group patients. However, employment status and recreational status did not differ significantly between medical and surgical groups. Total number of hospitalizations after randomization was higher in the surgical group owing primarily to rehospitalization during the first year of follow-up for the coronary artery bypass graft surgery. Risk factors, including high blood pressure, cigarette smoking, high cholesterol levels, overweight, and poor exercise habits remained similar between medical and surgical groups. This randomized collaborative study shows that coronary artery bypass graft surgery improves the quality of life as manifested by relief of chest pain, improvement in both subjective and objective measurements of functional status, and a diminished requirement for drug therapy. However, no significant effect on employment or recreational status was observed.