THERAPY AND PREVENTION CORONARY ARTERY DISEASE Coumadin and aspirin in prevention of recurrence after transluminal coronary angioplasty: a randomized study

To determine the influence of adjunctive treatment with coumadin or aspirin on recurrence rate after percutaneous transluminal coronary angioplasty (PTCA), 248 patients in whom PTCA was assessed to be a primary success were randomized to either 325 mm aspirin daily or to coumadin treatment sufficient to maintain a prothrombin time 2 to 2.5 times the control value. The follow-up protocol included stress testing and coronary angiographic examinations 3 to 6 months after PTCA. All patients were followed for at least 9 months. Of the 122 patients randomized to coumadin 44 (36%) had recurrent stenoses as opposed to 34/126 (27%) of patients on aspirin, a difference that did not reach statistical significance at the .05 level. However, patients with at least a 6 month history of angina demonstrated a significantly different response to adjunctive treatment in that 19/43 (44%) of coumadin patients as compared with 10/48 (21%) of aspirin patients had recurrent stenoses (p < .05). Thus, coumadin was not shown to be more effective than aspirin as adjunctive treatment after PTCA, while aspirin was shown to be superior to coumadin in patients with a longer history of angina. Circulation 69, No. 4, 721-727, 1984. AFTER REVASCULARIZATION PROCEDURES such as coronary artery bypass grafting and coronary angioplasty there is often recurrence of stenosis. Several adjunctive therapies have been recommended to prevent thrombus formation with closure of graft or vessel. Early investigators in angioplasty recommended the use of coumadin as long-term adjunctive therapy after femoropopliteal transluminal angioplasty with the Dotter technique.' Thereafter, coumadin therapy was also used for peripheral dilatation with the balloon technique2 and later applied in coronary angioplasty.3 Long-term patency of 75% was achieved in European patients with adjunctive coumadin therapy after percutaneous transluminal coronary angioplasty (PTCA). The use of coumadin therapy was also supported by selected studies of the effectiveness of anticoagulants in patients after myocardial infarction.5 6 Other studies demonstrated benefit from the administration of aspirin after infarction.7-9 Schneider et al.10 reported the results of a randomized study comparing aspirin and From the Department of Medicine and Radiology, Emory University School of Medicine and Emory University Hospital, Atlanta. Address for correspondence: Andreas R. Gruentzig, M.D., Emory University Hospital, 1364 Clifton Rd., Atlanta, GA 30322. Received April 25, 1983; revision accepted Dec. 8, 1983. *Presented in part at the 55th Scientific Session of the American Heart Association, Dallas, November 1982. Vol. 69, No. 4, April 1984 coumadin therapy in patients undergoing femoral endarterectomy or femoropopliteal bypass grafting. They concluded that patients undergoing endarterectomy benefited from aspirin therapy, whereas in patients with bypass grafts, coumadin was preferable. Later it became apparent that centers at which coumadin was not used had similar results with respect to long-term patency after PTCA,"1-'" as did centers at which this adjunctive therapy was used. In the face of this controversy, our study was undertaken to evaluate the effectiveness of these two adjunctive therapies in preventing recurrent stenosis after coronary dilatation by means of a randomization process and in cooperation with referring physicians.