[Site and shape of the most severe stenoses in coronary arteries and their relationship to the risk factors. Postmortem findings (author's transl)].

Out of a great number of hearts investigated post-mortem by coronary arteriography and quantitative histology, 437 coronary arteries of 202 hearts had severe stenoses with a lumen reduction to less than 50 per cent. Mainly these most severe obstructions lay between 2 and 5 cm behind the aortic ostium. In the right coronary artery the frequency curve showed a smaller peak, a smaller decrease, and an inconsiderable second peak in the periphery. Perhaps the slow calibre reduction of the right coronary artery is significant for these findings. The narrowed lumen mostly lay a little eccentric and had an oval shape. A slit-like shape was a rare finding. Only in 20 per cent of the severe stenoses a normal intima was preserved in parts of the circumference of the coronary artery. Among 113 patients the following risk factors were known: hypertony, diabetes mellitus, cigarette smoking and hypercholesterinemia. Significant differences in the localisation of the most severe stenoses were not recognizable under the influence of these risk factors.