Haemostatic function in patients undergoing coronary artery bypass grafting: Peroperative perturbations and relations to saphenous vein graft closure

Vein graft failure remains a major problem after coronary artery bypass gra fting. Occlusion in the first weeks usually is caused by thrombosis, wherea s intimal hyperplasia and eventually atherosclerotic changes with superimpo sed thrombus formation underlie subsequent closure. The present investigati on was conducted as a pilot study to examine whether perturbations of haemo static function predispose to early saphenous vein graft occlusion after co ronary artery bypass grafting. Pre- and postoperative determinations (perfo rmed on the first, third, and sixth postoperative days) of haemostatic fact ors and inhibitors were related to the presence of graft occlusion assessed by angiography at 3 months after surgery in 100 men undergoing elective co ronary artery bypass grafting for stable angina pectoris. Occlusion of one or more vein grafts within three months of surgery occurred in 23 of the 10 0 patients examined. The percentage increase in plasma plasminogen activato r inhibitor-1 activity on the first postoperative day was significantly hig her in patients who subsequently were found to have vein graft occlusion (p <0.05). Otherwise no postoperative haemostatic measurements were found to p redict early vein graft closure. A perturbed plasma plasminogen activator i nhibitor-1 response to coronary artery bypass grafting tentatively could be added to the vessel-specific factors that remain the main determinants of early vein graft closure. (C) 2000 Elsevier Science Ltd. All rights reserve d.