Clinical characteristics and coronary anatomy in refractory unstable angina pectoris leading to coronary artery bypass grafting. The Kuopio experience.

One hundred patients with high-risk unstable and medication-resistant angina pectoris underwent coronary artery by-pass grafting. In 35 cases the angina was of early post-infarction type, in 60 it was progressive after previous stability and in five it was of recent onset. All had abnormal ECG in association with anginal attacks (ST depression in 76, ST elevation in 5, T-wave inversion in 15 and left bundle branch block in 4). The left main coronary artery was stenosed in 33 patients, and the respective figures for three-vessel, two-vessel and one-vessel disease were 53, 9 and 5. The average number of inserted peripheral grafts/patient was 4.6. The perioperative mortality rate was 1%. Seven patients had confirmed or probable perioperative myocardial infarction and two had late infarction during the hospital stay, but none had angina pectoris on discharge. Of 60 patients re-examined after 1 year, 47 were angina-free. Five had NYHA class III angina, but all were improved. In refractory unstable angina pectoris there is severe coronary artery involvement, but bypass grafting can give good results.