A large study just published in JAMA has found that the most common arrhythmia, atrial fibrillation (AF), long known to be a sequela of a variety of cardiac ailments, may also play a causal role in provoking heart attacks.
The study s authors, Eric N. Prystowsky, MD and Edward T. Fry, MD, from St. Vincent Medical Center in Indianapolis, studied over 23,000 subjects, among whom 1,631 had prevalent AF, while the remaining 22,000-plus were free of any heart disease, including arrhythmia. Over the course of the subsequent 5 years (median time of the study), those with AF had about a two-fold increase in the incidence of heart attack (myocardial infarction, MI) as compared to those without AF. This increased risk was found even when all other cardiac risk factors were controlled for. Interestingly, the older subjects (>75 years) had no increased risk as compared to the younger subjects. However, the increased risk was more prominent in women and in blacks, as compared to men and whites, respectively.
ACSH s Dr. Gil Ross had this perspective: When I was in practice some (ahem) time ago, we didn t worry over-much about AF. This is interesting from a historical perspective, as the pendulum has swung strongly towards intense concern about the consequences of AF. We have accumulated much data on the risk of embolic stroke and the need to keep AF patients anti-coagulated to prevent such catastrophes. We knew of course that CAD patients were (and are) at high risk of developing AF. Now it seems that AF patients are, conversely, at risk of having an MI. So the message is: treat patients with AF as if they were vulnerable to MI no matter what other history they have, including warnings to stop smoking (as always), aggressively treat high blood cholesterol and pressure, and aspirin daily.
