Harvard Heart Letter
Duration of atrial fibrillation and risk of stroke
Research we’re watching Episodes of atrial fibrillation (afib) — a chaotic, irregular heart rhythm — can last for minutes, hours, days, or much longer. The condition encourages blood clots to form in the heart; the clots can then escape and lead to a stroke. New research suggests that even intermittent bouts of afib (which were previously considered to be low risk) may increase a person’s risk of stroke.