Platelet inhibitors versus anticoagulants for prevention of aorto-coronary bypass graft occlusion

The effects of the antiaggregant substance ticlopidine and ofthe anticoagulant acenocoumarol on patency rates of aorto-coronarybypass grafts were compared in a prospective randomized trial.Ticlopidine, 250 mg b.i.d. was administered orally from thefirst postoperative day till angiography, while anticoagulationwith acenocoumarol was initiated on the second to third postoperativeday. Side-effects of ticlopidine were rare and patient managementwith the standard dosage of this drug was easier than oral anticoagulation.From an initial group of 166 randomized patients 149 completedthe trial by coronary angiography three months postoperatively.The 78 patients in the ticlopidine group showed a complianceof 85%. The average prothrombin time in the 71 patients receivingacenocoumarol was 26.9%. Detailed statistical analysis of thetwo study groups revealed no reason to doubt the correctnessof randomization. Coronary angiography showed an average patency rate per patientof 84% with ticlopidine and of 82% with acenocoumarol. Thisand various other measures of graft occlusion did not revealany substantial difference in graft patency of patients receivingticlopidine or acenocoumarol. It is concluded that ticlopidinemay well be used instead of anticoagulants forprevention ofpostoperative occlusion of aorto-coronary bypass grafts