Nonvalvular atrial fibrillation as a cause of fatal massive cerebral infarction in the elderly.

By studying 3,408 consecutive autopsied elderly patients, we found that two thirds of the 132 massive cerebral infarctions (86) were embolic, of cardiac origin. Embolic infarction associated with nonvalvular atrial fibrillation was seen in 48 cases (36%), half due to the first stroke. Embolic infarction associated with heart disease other than nonvalvular atrial fibrillation was seen in 23 cases (17%), and that from nonbacterial thrombotic endocarditis was seen in 15 cases (11%). Thrombotic infarction or infarction of nonembolic cardiac origin was found in only 39 cases (30%). Of 56 patients with fatal massive cerebral infarction who died less than or equal to 2 weeks after their stroke, 25 (45%) had embolic strokes associated with nonvalvular atrial fibrillation. Our study shows that nonvalvular atrial fibrillation is a very important cause of fatal massive cerebral infarction in the elderly.