One-hundred-forty patients with atrial fibrillation (AF) due to non-rheumatic, non-valvular heart disease (NVHD) who suffered a cerebral infarct were identified. Fifty-three (38%) died of the initial stroke. The surviving patients were followed up to 9 years without anticoagulant therapy. In the 59 patients available for follow-up, the risk of recurrent cerebral ischemia remained at approximately 20% per year throughout the 9 year observation period. The recurrence rate was the same regardless of age, sex, previous myocardial infarction, or whether chronic AF or intermittent AF were present. Only 7 (12%) died from a second stroke, however. The high annual rate of recurrence and lack of controlled therapeutic trials in this population of patients warrant a prospective study to define the benefits and relative risks of anticoagulant therapy in AF due to NVHD.