Abstract 3300: Aspirin and Medium Intensity Coumadin versus Aspirin Alone in the Prevention of Reocclusion After Successful Thrombolysis for Suspected Acute Myocardial Infarction: 5-Year Follow-Up of the APRICOT-2 Trial
Background: The Antithrombotics in the Prevention of Reocclusion In COronary Thrombolysis (APRICOT)-2 trial showed that medium intensity coumadin (INR 2–3) added to aspirin reduces angiographic and clinical reocclusion in the first three months after successful thrombolysis. This analysis assesses whether the observed early clinical benefit is sustained at 5-year follow-up.
Methods: In the APRICOT-2 trial 251 patients (< 76 yrs) with TIMI 3 flow within 48 hours after thrombolysis for STEMI were randomized to treatment with aspirin 80 mg plus medium intensity coumadin (INR 2–3) or aspirin alone until follow-up angiography, scheduled at three months. Five-year clinical follow-up was collected.
Results: Reocclusion rates (TIMI flow <3) were 15% (19/123) in patients on the combined antithrombotic regimen (median INR 2.6) and 28% (36/128) in patients on aspirin alone (RR 0.55; 95% CI 0.33– 0.90, p<0.02). Three-month survival rates free from reinfarction and revascularization were 86% and 65%, respectively (p<0.01). In 84% of patients complete 5-year clinical follow-up was available. Five-year survival without reinfarction or revascularization was 61% in patients on combination therapy and 41% in patients on aspirin alone (log-rank p<0.01, Figure⇓). Event-free survival rates were 33% in patients with reocclusion vs 56% in patients with sustained patency (p<0.01).
Conclusions: The early clinical benefit from medium intensity coumadin added to aspirin after successful thrombolysis is sustained at five-year follow-up. This benefit is attributed to a reduced risk for reocclusion. These observations support a role for prolonged anticoagulation in this setting.