Acute myocardial infarction without obstructive coronary artery disease demonstrated by selective cinearteriography.

Among iI8 patients who had had a well-documented acute myocardial infarction and who were studied by selective coronary arteriography, inS cases (4'2%) no obstructive lesions of the coronary arteries could be detected. The left ventricular angiogram showed an abnormal contraction pattern in 3 instances. The electrocardiogram and vectorcardiogram showed infarct patterns in 3 cases and transient disturbances of repolarization in 2. Of the latter, one patient developed an infarction with classical electrocardiographic picture Io months later. A second coronary arterio- gram was made which showed a total obstruction of the anterior descending artery. Gradually the electrocardiographic alterations vanished; a third coronary arteriogram made after another i8 months revealed partial recanalization of the obstructed artery. It seems that a primary thrombo- embolic process could be responsible for the disease pattern. After the first coronary arteriogram appeared normal, anticoagulant therapy was discontinued; in retrospect the very normality of the arteriogram in conjunction with the typical clinical picture of myocardial ischaemia probably should have constituted an indicationfor permanent anticoagulant therapy. In this case the serum enzymes never reached pathological levels. In all the other cases the enzymes showed characteristic increases. One of these cases was that of a 33-year-old woman who was 36 weeks pregnant when the infarction occurred. A spontaneous and uncomplicated delivery of a healthy childfollowed 3 weeks later. Coronary angiography revealed an aneurysm of the anterior descending artery with- out narrowing. It is possible that the aneurysm had originated as a dissecting aneurysm which temporarily occluded the lumen. In the remaining 3 cases no specific features suggesting an aetiological explanation were found. Some possible underlying causes are discussed.