Long-term Prognosis of Prior and New-Onset Atrial Fibrillation in ST-Elevation Myocardial Infarction Patients Undergoing Percutaneous Coronary Intervention

Background: Atrial fibrillation (AF) is a well-known complication in the setting of ST Elevation MI (STEMI) and is associated with increased 30-day mortality. However, data on the long-term prognostic implications of New-Onset AF (NOAF) complicating STEMI in the era of complete revascularization remain controversial. Our aim therefore was to evaluate the long-term prognosis of prior AF and new-onset AF (NOAF) in STEMI patients undergoing percutaneous coronary intervention (PCI).

Methods: Among 1657 consecutive patients hospitalized in our Cardiac Intensive Care Unit (CICU) with STEMI during the 7-year period of 2008-2014, we reviewed patients for the existence of prior AF and New Onset OAF (NOAF). NOAF was defined as AF occurring within 30 days of the STEMI episode. These AF groups were compared with a Control Group consisting of patient without this phenomenon.

Results: Within our cohort 75 (4.5%) patients had AF prior to hospitalization, while 52 (3.1%) had NOAF0. Patients with AF were older with reduced systolic function. Patients were followed for a mean of 7.5 years. Overall mortality during follow up was 172 (10.4%), of those 42 (2.5%) died within 30 days. Thirty days mortality and All-Cause mortality rates were higher in patients with prior AF in compare to those without (10.7% vs. 2.1% p=.00 and 32.0% vs. 9.4%, p=.00, respectively). NOAF, was also associated with high all-cause mortality rates (17.3% vs. 9.1%, p=.05) but not with 30-days mortality statistical significance. In multivariate analysis, prior AF but not NOAF was a predictor of mortality throughout the follow-up period (HR 1.9, 95% CI 1.2 to 3.1, p=.005 and HR 0.9, 95% CI 0.4 to 2.0, p=.89, respectively).

Conclusion: The presence of prior AF, but not of new-onset AF, in STEMI patients treated with PCI is associated with increased 30-day and long term mortality rates.