Outcome of patients in relation to duration of new-onset atrial fibrillation following acute myocardial infarction.

Aim: The duration of new-onset atrial fibrillation (AF) following the acute myocardial infarction (AMI) was evaluated as well as its relation to in-hospital and 7-year mortality.

Methods And Results: A total of 320 consecutive patients with AF following AMI were examined and patients with AF <7 h (n = 141) were compared to those with AF > or =7 h in duration (n = 179). Receiver Operating Characteristic analysis was performed to identify the most useful AF duration cut-off level for the prediction of poor outcome. Patients with longer AF duration were older and had more advanced heart failure than patients with short arrhythmia duration. Patients with longer AF duration had worse outcome, including higher in-hospital (22.3 vs. 12.8%) and 7-year (67.4 vs. 34.4%) mortality. After multivariate adjustment, longer AF duration remained an independent predictor of long-term mortality (relative risk = 2.04, 95% confidence interval = 1.39-2.99, p = 0.0002).

Conclusion: New-onset AF > or =7 h in duration following the AMI independently predicts long-term mortality.