Effects of warfarin, aspirin and the two combined, on mortality and thromboembolic morbidity after myocardial infarction - The WARIS-II (Warfarin-Aspirin Reinfarction Study) design

The efficacy and safety of warfarin, aspirin, and the two combined are comp ared in a long-term, randomized, open, multicentre study involving 3606 pat ients after acute myocardial infarction (1202 in each treatment group). In this trial three groups receive either warfarin, aimed at a therapeutic lev el of the international Normalized Ratio (INR) 2.8-1.2, or 160 mg aspirin d aily, or 75 mg aspirin daily combined with warfarin with INR 2.0-2.5. A pla cebo group is not included. patients are screened before randomization and are given major examinations at 4 weeks and at the end of the study. In add ition, all patients rue given a questionnaire every 6 months. Composite end points include death, non-fatal reinfarction and cerebral stroke. All analy ses are conducted on the intention-to-treat principle and on on-efficacy ba sis. The analyses control for recruiting centre, use of beta blockade, use of thrombolytic therapy and use of angiotensin converting enzyme (ACE) inhi bitors.