Results from the study, which looked at over 69,255 patients with AMI enrolled in the NCDR^® ACTION Registry^® – GWTG™, found that only 32.5 percent of patients with AFib were taking warfarin before being admitted to the hospital for MI. Within this population, use of warfarin at discharge increased with higher congestive heart failure, hypertension, age, diabetes, stroke [doubled] (CHADS2) risk strata (28.5 percent, 34.6 percent, and 43.5 percent for CHADS2 scores 0, 1, and ≥2; P < .001) and increased in patients at low, intermediate, and high risk of bleeding (25.4 percent, 42.3 percent, and 42.1 percent; P=.004). Of those not discharged with warfarin, less than 72.5 percent received clopidogrel, even when clopidogrel was recommended post-MI. "This was surprising, because clopidogrel is recommended after acute myocardial infarction and provides additional benefits in a population with atrial fibrillation not receiving warfarin," the authors said.