New-onset Atrial Fibrillation in Patients Presenting with Acute Myocardial Infarction

Background Atrial fibrillation (AF) can be seen secondary to the complications after acute myocardial infarction (AMI), but it has a poor prognosis when occurs independently. These patients are prone to an increased risk of all in-hospital major cardiac complications and also at an increased risk of mortality. Therefore, it is important to quantify the burden of this aggravating complication in an otherwise lethal manifestation of acute coronary syndrome. The aim of this study was to find the frequency of AF in patients presenting with AMI and the factors associated with it. Methods We conducted this observational study on 216 patients who presented with AMI at the largest cardiac center of Karachi, Pakistan from July 2014 to January 2015 with AMI without a past history of AF. Patients underwent routine clinical assessment and laboratory investigations. Atrial fibrillation, detected on electrocardiographic assessment at the time of admission or during hospital stay without a prior history of persistent atrial flutter or paroxysmal atrial fibrillation, was classified as new-onset atrial fibrillation (AF). Results We selected a total of 216 patients, 117 (54.2%) male and mean age of 50.76 ± 6.00 years. Diabetes was found in 140 (64.8%), 164 (75.9%) were hypertensive, and 61 (28.2%) patients were smokers. ST-segment elevation myocardial infarction (STEMI) was diagnosed in 97 (44.9%) patients. The new onset of atrial fibrillation was found in 27 (12.5%) of the patients with AMI. Univariate analysis revealed a statistically significant association of new-onset AF with hypertension. Conclusion The new onset of atrial fibrillation was found in 12.5% of the patients presented with acute myocardial infarction. It is a significant complication in term of its frequency in AMI and it is more common in hypertensive patients.