Prevention of stroke in chronic and recurrent atrial fibrillation: role of the emergency department in identification of "at-risk" patients

The objective was to determine the proportion of patients presenting to the Emergency Department (ED) in atrial fibrillation (AF) who are at high risk of thromboembolic stroke as defined by the American Heart Association and who might benefit from anticoagulation therapy. We enrolled all patients identified as having AF between 28th June 1999 and 26th March 2000. Data collected included demographic information, presenting complaint, discharge diagnosis, risk factors for thromboembolic stroke, contraindications to anticoagulation (as defined by the Stroke Prevention in AF Investigators), admission and discharge medications, and cardiac rhythm on presentation and at discharge. 193 patients were identified within the study period. Two patient histories were not available for review. 121 patients had a prior history of AF. Of these, 65 patients were at high risk for thromboembolic stroke and had no contraindication to anticoagulation therapy 43 (66%) were on Warfarin at presentation but 14 (22%) were on Aspirin and 8 (12%) were on neither. 34% of patients with chronic atrial fibrillation presenting to the ED, at high risk of thromboembolic stroke and without contra-indication to anticoagulation, were not anticoagulated on presentation. ED attendance provides an opportunity for intervention for the prevention of stroke in this group.