[Variations of distribution of the coronary arteries (apropos of 3,000 coronarographies)].

The various types of anomalous origin and unusual course and/or predominance of the coronary arteries encountered in a review of 3 000 selective coronary arteriograms were studied. 1. Abnormal ostia: Ectopic ostia with anterior, posterior or lateral displacement (11 cases). Variations in the number of ostia:--accessory ostium for the conus branch (68 cases);--distinct ostia for LAD and circumflex artery (21 cases);--single coronary artery (6 cases). 2. Abnormal course of coronary arteries: Anomalous circumflex origin from the right coronary artery (8 cases). Unusual predominance of the left coronary artery:--right predominance 74,5 %;--left predominance 14 %;--balanced 11,5 %. In aortic stenosis, the frequency of these different malformations is very different. Different patterns of vascularizattion of the centers of automatism and of the left ventricular free wall were also studied.