Postoperative changes in aortocoronary saphenous vein grafts revisited: angiographic studies at two weeks and at one year in two series of consecutive patients.

Comparison of aortocoronary saphenous vein graft status at two weeks and at one year was made in two series of patients. The early postoperative evaluation includes 122 patients of the first 138 operated in our institution (182 grafts) and 83 subjects from a second series of 100 patients operated after modifications of surgical techniques (184 grafts). The one-year follow-up study was obtained in 105 patients of the first series (154 grafts) and in 67 of the second (152 grafts). The patency rate at two weeks was not significantly different between the two groups: 86.3% vx. 91.8%. A marked decrease of steonses noted early at anastomotic sites was observed: 15% to 5.5% (P less than 0.025). The patency rate at one year improved from 67% to 85,5% (P less than 0.0005). Grafts having flows at operation of at least 50 ml/min had patency rates of 90% in both series. The patency in grafts with initial flows below 50 ml/min increased from 28% to 73% (P less than 0.005). The incidence of late localized graft stenoses greater than 40% decreased from 16.5% to 6% (P less than 0.025), and diffuse narrowing greater than 40% was found in only 12% of the patent grafts at one year in the second series as compared to 31% in the first (P less than 0.001). These improved results do not appear to have been influenced by selection favoring better distal run-off in grafted arteries nor by the introduction of sequential grafts to multiple coronary arteries in the second group. Modified surgical techniques may explain the improved results.