Mechanisms of occlusion of saphenous vein--coronary artery "jump" grafts.

Seven patients with 12 end-to-side and eight side-to-side saphenous vein graft-to-coronary artery anastomoses were studied at autopsy. Postmortem coronary arteriograms and serial histologic sections of the anastomoses were performed. Occlusive changes occurring in the coronary arteries tended to be at the ends of the arteriotomy and could be attributed to reduction of arterial circumference from its eversion and utilization in the anastomotic connection, or from thrombosis along the suture line or from both. The mechanisms of arterial occlusion were the same in side-to-side and end-to-side anastomoses. In addition to the occlusive changes at the anastomosis, "jump" grafts with two anastomoses were susceptible to rolling or kinking of the graft, apparently as a result of torsion from placement of the side-to-side anastomosis.