Risk is highest when AF develops more than 1 month after MI.

The effect of atrial fibrillation (AF) on prognosis in myocardial infarction (MI) patients is unclear. In this cohort study, Minnesota investigators identified 3220 patients hospitalized with first MIs and identified them as having (1) no AF, (2) AF before MI, or (3) AF within 2, 3–30, or >30 days after MI.


In 304 patients, AF preceded MI; in 729 patients, AF developed during or after MI (most commonly >30 days after MI). AF during or after MI was associated with older age, hypertension, female sex, diabetes, and chronic kidney disease, as well as with anterior MI, lower ejection fraction, and higher Killip class. AF after MI was associated with elevated risk for death (hazard ratio, 3.8) during a mean follow-up of 6.6 years. Mortality adjusted for clinical factors varied according to the timing of AF and ranged from an HR of 1.5 for those with prior AF to 2.6 in those who developed AF >30 days after MI.


Citation(s):

Jabre P et al. Atrial fibrillation and death after myocardial infarction: A community study. Circulation 2011 May 17; 123:2094.

Lubitz SA et al. Atrial fibrillation and death after myocardial infarction: Risk marker or causal mediator? Circulation 2011 May 17; 123:2063.