Background:
Little data are available regarding differences in prognosis and health status between new-onset and prior atrial fibrillation (AF) among patients with acute myocardial infarction (AMI).
Methods:
The TRIUMPH study enrolled 4340 AMI patients who received longitudinal follow-up including SF-12 health status assessments through 1 year post-AMI. We compared 1-year mortality, rehospitalization, and functional status according to AF type (none, prior, new) after adjusting for differences in baseline characteristics.
Results:
A total of 212 AMI patients (4.9%) had prior AF and 254 (5.9%) had new-onset AF. Compared with no AF, new AF was associated with older age, male sex, first MI, worse baseline physical function, home atrioventricular nodal blocker use, and worse ventricular function (c-index 0.77). Rates of 1-year mortality were 6.2%, 14.5%, and 13.0%, and 1-year rehospitalization rates were 29.1%, 44.2%, and 36.8% for no, prior, and new AF, respectively. After multivariable adjustment, neither prior nor new AF was associated with increased 1-year mortality, and only prior AF was associated with increased risk of 1-year rehospitalization (Figure). After adjusting for baseline SF-12 physical function scores, patients with prior AF had lower 1-year scores than those with no AF (40.6 vs. 43.7, p <0.003), whereas patients with new AF had similar scores (42.9 vs. 43.7, p=0.36).
Conclusion:
New-onset AF during AMI is associated with a number of comorbidities but, unlike prior AF, is not associated with adverse outcomes. These results raise the question of whether AF is itself a cause of or simply a marker of comorbidities leading to downstream adverse outcomes after AMI.
Physical function and independence 1 year after myocardial infarction: Observations from the Translational Research Investigating Underlying disparities in recovery from acute Myocardial infarction: Patients' Health status registry