Significance of Atrial Fibrillation Complicating ST-Segment Elevation Myocardial Infarction

The aim of the present study is to assess the clinical impact of atrial fibrillation (AF) in patients with ST-segment elevation myocardial infarction (STEMI) complicated by new-onset AF depending on STEMI location and timing of arrhythmia. We analyzed 4,363 consecutive STEMI patients treated invasively. Finally, 4,099 subjects were included into further analysis, as 264 patients were excluded because of previous AF history. In total, 1,800 (43.9%) subjects with anterior infarction were included into Group 1, whereas Group 2 encompassed 2,299 (56.1%) patients with nonanterior infarction. Subsequently, both groups were divided into patients with new-onset AF (AF Group 1 and 2, respectively) and without AF (Control Group 1 and 2). New-onset AF was recognized in 225 patients (5.5%): 96 (5.3%) with an anterior wall infarction (AF Group 1) and 129 (5.6%) with a nonanterior wall infarction (AF Group 2). The incidence of early-onset arrhythmia (within 24 hours after admission) was significantly higher in AF Group 2 than in AF Group 1: 71.3% versus 35.4% (p