[Surgical treatment of coronary circulation disorders].

The objectives of aorto-coronary bypass surgery are threefold: relief of angina pectoris, increase in exercise performance and prolongation of life. The effect of surgery on ischemic pain and exercise tolerance is widely accepted, but the influence of bypass grafting on life expectancy is still controversial. Recent results of prospective randomized trials, however, have shown significantly better survival for surgically treated patients with specific anatomic characteristics such as left main disease and three-vessel disease. Among the operative risks, hospital mortality (1% in our experience) and incidence of perioperative myocardial infarction (around 5%, usually asymptomatic clinical course) have decreased with growing surgical practice and application of cold cardioplegia. Postoperative angiographic studies reveal 85% to 90% graft patency rate at one year; later the mean annual occlusion rate is reported to be less than 3%. The aorto-coronary bypass operation is indicated mainly for the following two groups of patients: 1. those in whom angina or drug therapy results in a restriction of working capacity or an undesirable change in lifestyle despite appropriate medical treatment; 2. the two subsets of patients being exposed to a particularly high risk of myocardial infarction or sudden death: patients with left main disease and patients with three-vessel disease. The benefits of coronary bypass surgery depend on several conditions: major determinants are completeness of revascularization, suitability of distal coronary segments for bypass grafting, and degree of ventricular impairment.