[Primary coronary artery dissection: its incidence and genesis studied by clinical and coronary angiographic findings].

The incidence and genesis of primary coronary artery dissection which occurred spontaneously in the coronary artery system were elucidated in this study. We examined clinical and coronary angiographic features of the patients who presented this dissection. Primary coronary artery dissection was observed in 23 (0.43%) of 5,400 consecutive patients with ischemic heart disease undergoing coronary angiography. The basic diseases were myocardial infarction in 17 cases and angina pectoris in 6. Sixteen patients (70%) had smoking habits, which might be related to this disease. The dissection of the right coronary artery in 12 cases, of the left anterior descending artery in 10, and of the left circumflex artery in only one was found. All lesions occurred in the proximal positions of the coronary branches. Seven (30%) of all cases had fixed coronary stenosis in other coronary branches. The other cases had "one-vessel" disease. Seventeen patients were treated medically, 5 had PTCA therapy and one had CABG operation. All the patients, except one who died of cancer are surviving in a 3.8-year follow-up. Patients can be divided etiologically into three groups. The first was comprised of those in the post- or peri-partum period. The second was those associated with coronary vasospasm, and the third was those with atherosclerotic coronary artery disease. The third group was the most frequent.