Outcomes and prognostic impact of prophylactic oral anticoagulation in anterior ST-segment elevation myocardial infarction patients with left ventricular dysfunction

Background-the contemporary role of prophylactic anticoagulation following extensive anterior wall st-segment myocardial infarction (stemi) is unclear. methods and results-we evaluated anterior stemi patients with left ventricle dysfunction (left ventricular ejection fraction ≤40%) (high risk),categorized by prophylactic warfarin use,within a regional stemi. patients with pre-existing atrial fibrillation were excluded. the primary outcome was an adjusted (for global registry of acute coronary events risk score) 1-year composite of recurrent ischemia,stroke/transient ischemic attack/systemic embolism,or all-cause death. of the 2032 stemi admissions,436 (21.5%) were high risk. after excluding 19 (4.4%) patients with definite left ventricle thrombus and 21 (4.8%) in-hospital deaths (2 had left ventricle thrombus),prophylactic warfarin was utilized in 236/398 (59.3%) high-risk survivors. prescriptions were comparable across sex,but recipients were on average younger (58.5 years versus 64.0 years,p < 0.001) and lower risk (global registry of acute coronary events risk: 163 versus 181,p < 0.001). no association on the adjusted ischemic composite (23.3% versus 25.3%,odds ratio 0.96,95% ci 0.60-1.55) or thromboembolic events (2.1% versus 1.2%,odds ratio 1.99,95% ci 0.38- 10.51) was observed,but reduced 1-year all-cause mortality was noted (2.5% versus 8.6%,odds ratio 0.30,95% ci 0.11-0.81); numerically higher major bleeding was observed at 1 year (2.5% versus 1.2%,odds ratio 2.17,95% ci 0.43-10.96). conclusions-a high utilization of prophylactic warfarin occurs in anterior stemi patients with left ventricle dysfunction,yet appears to provide no additional benefit on the ischemic composite. the association with lower all-cause mortality,but higher bleeding,calls for an improved understanding of its role in high-risk stemi. © 2017 the authors.