Prognostic risk of atrial fibrillation in acute myocardial infarction complicated by left ventricular dysfunction: the OPTIMAAL experience.

AIMS The present study aimed to determine the frequency and the impact on clinical outcome of atrial fibrillation (AF) in patients with acute myocardial infarction (AMI) and left ventricular dysfunction. METHODS AND RESULTS In the OPTIMAAL trial, 5477 patients with AMI and signs of left ventricular dysfunction were included. At baseline, 655 patients (12%) had AF, and 345 (7.2%) developed new-onset AF during follow-up (2.7 +/- 0.9 years). Older patients, patients with history of angina and worse Killip class had and developed AF more frequently (P < 0.001). Patients with AF at baseline were at increased risk relative to those without AF for mortality [adjusted hazard ratio (HR) of 1.32, P = 0.001] and for stroke (HR 1.77, P < 0.001). New-onset AF was associated with increased subsequent mortality for the first 30 days following randomization (HR 3.83, P < 0.001) and the entire trial period (HR 1.82, P < 0.001). Risk of stroke was increased for the first 30 days (HR 14.6, P < 0.001) and for the whole trial period (HR 2.29, P < 0.001). CONCLUSION AF is frequently observed in patients with AMI complicated by heart failure. Current AF, and the development of new AF soon after AMI, is associated with increased risk of death and stroke.