APROTININ IN AORTOCORONARY BYPASS-SURGERY - INCREASED RISK OF VEIN-GRAFT OCCLUSION AND MYOCARDIAL-INFARCTION - SUPPORTIVE EVIDENCE FROM A RETROSPECTIVE STUDY

To assess the thrombotic risk of aprotinin in aortocoronary bypass sur gery, we retrospectively analyzed the results of a trial, originally d esigned to compare the effects of one-year treatment with various anti thrombotic drugs in the prevention of vein-graft occlusion. Graft pate ncy at one year was assessed by angiography. Myocardial infarction, th romboembolism, major bleeding, and death were clinical endpoints. Of 9 48 randomized patients, 42 received aprotinin, all enrolled by one of the participating centres. Occlusion rates of distal anastomoses were 20.5% in the aprotinin group and 12.7% in the non-aprotinin group (p = 0.091). The proportions of patients with occluded grafts were 44.1% v ersus 26.3% (p = 0.029). Perioperative myocardial infarction occurred in 14.3% and 7.0%, respectively (p = 0.12). Mean postoperative blood l oss was 451 mi in the aprotinin group compared with 1039 mi in the non -aprotinin group (p < 0.0001). Mean transfusion requirements were 1.1 U versus 2.1 U of red blood cells (p = 0.004). Aprotinin decreases blo od loss and transfusion requirement. Our data suggest that this benefi t may be associated with a reduction of graft patency and an increased risk of myocardial infarction.