Posted on 11/26/2012

Atrial fibrillation may raise the risk of sudden cardiac death, according to findings from two large population-based cohorts, according to a report in MedPage Today.

The risk of sudden cardiac death was elevated 3.26-fold with incident atrial fibrillation in multivariate analysis of the ARIC (Atherosclerosis Risk in Communities) study, Lin Y. Chen, MD, MS, of the University of Minnesota Medical School in Minneapolis, and colleagues found.

And the risk was 2.14 times higher after onset of Afib in the Cardiovascular Health Study (CHS), the group reported online in the Archives of Internal Medicine.

If confirmed, the sudden cardiac death finding "adds to our evolving understanding that Afib is not a benign condition," they wrote.

"Not only does atrial fibrillation predispose to stroke, heart failure, and death, but the arrhythmia per se may increase the risk of death from ventricular tachyarrhythmias. The latter is potentially preventable; to this end, additional research to identify predictors of sudden cardiac death in patients with atrial fibrillation is much needed."

The analysis included 15,439 adults ages 45 to 64 at baseline in four communities in the ARIC Study followed periodically with examinations and annually via telephone calls and another 5,479 Medicare beneficiaries at four sites in the CHS cohort, which was originally designed to look for coronary heart disease risk factors and stroke.

Incidence of sudden cardiac death was:

  • In ARIC, 2.89 per 1,000 person years with atrial fibrillation versus 1.30 without it
  • In CHS, 12 per 1,000 person-years with atrial fibrillation versus 3.82 without it

In a meta-analysis of the two studies, incident atrial fibrillation was associated with a 2.47-fold elevation in likelihood of sudden cardiac death (95% CI 1.95 to 3.13).


SOURCE: MedPage Today