Enlarged heart chamber linked to higher stroke risk
Stroke risk was 11.1% in people with an enlarged left atrium, the heart’s upper left chamber, versus 4.6% in those without enlargement.
The observational study followed 10,024 participants from the Copenhagen General Population Study, with a mean age of 60; 57% were women. None had atrial fibrillation, an irregular heartbeat, at the start. Participants underwent heart scans between 2010 and 2018. Researchers measured the volume of the left atrium, the heart’s upper left chamber, relative to body size. They used separate cutoffs for men and women to define enlargement.
Over a median follow-up of 7.3 years, 356 participants had a stroke. Left atrial enlargement was linked to higher stroke risk after adjustment for other factors. The association remained similar after researchers accounted for newly occurring atrial fibrillation. Enlargement was also linked to atrial fibrillation and heart failure, but not dementia or death from any cause.
Why it matters
Stroke is an age-related disease. The study addresses whether heart structure may help identify risk that is not captured by atrial fibrillation alone.
Caveats
This observational study cannot show that an enlarged left atrium caused strokes or rule out other explanations for the association.
The paper
Left Atrial Enlargement Identifies Risk of Stroke Independent of Atrial Fibrillation
The Heart Centre Copenhagen University Hospital - Rigshospitalet Denmark
Journal of the American Heart Association, 10 Oct 2026
