Detection of atrial fibrillation in patients with acute stroke.

Atrial fibrillation (AF) and paroxysmal AF (PAF) are common causes of stroke which may not be detected by a single electrocardiogram (EKG). We conducted a prospective study to determine if 48 hours of telemetry monitoring increased the rate of detection of AF in patients with acute stroke and thus identified patients requiring anticoagulation. One hundred and fifty consecutive patients with acute ischemic stroke were placed on telemetry monitoring for 48 hours. Thirty-five patients had AF related strokes. There were 12 patients with AF related stroke who did not have a previous history of AF and were found to have AF following the stroke. Six of these 12 patients were found to have AF on their admission EKG. The remaining six patients had normal admission EKGs and were diagnosed with AF only during telemetry monitoring for 48 hrs. Patients with AF were older, had larger strokes, which were more likely to be non-lacunar, than patients without AF. Our study suggests that AF is sometimes undiagnosed until a stroke occurs. Improved methods of detection of AF are needed in high-risk patients for primary stroke prevention. Patients older than 65 years of age with non-lacunar strokes should have 48 hours of telemetry monitoring to detect previously undiagnosed AF.