Prolonged ambulatory cardiac monitoring improved AF detection, treatment after cryptogenic stroke

Prolonged ambulatory cardiac monitoring after a cryptogenic ischemic stroke or transient ischemic attack appears to be a more effective method for detecting occult atrial fibrillation than standard methods.

In the largest randomized trial to evaluate whether longer ECG monitoring is beneficial after stroke, researchers for the EMBRACE trial assigned patients to wear an event-triggered cardiac monitor for up to 30 days or a repeat 24-hour Holter monitor to record AF events. The trial included 572 patients (mean age, 73 years) who had a recent cryptogenic ischemic stroke (63%) or TIA (37%) and no known AF after standard diagnostic interventions that included a negative Holter monitor.

David J. Gladstone

David J. Gladstone, MD, PhD, assistant professor, department of medicine, division of neurology, University of Toronto, Canada, and colleagues investigated the primary outcome of ≥1 AF episode lasting at least 30 seconds within 90 days of randomization and secondary outcomes of patient compliance and anticoagulation status.

According to results presented at the International Stroke Conference 2013, AF was detected in 16% of patients in the prolonged monitoring group compared with 3% in the repeat 24-hour Holter monitoring group (P<.001). In the prolonged monitoring group, 82% completed ≥3 weeks of monitoring; the majority of AF episodes were captured during the first 2 weeks of monitoring.

At 90 days, anticoagulant use had increased and was greater in the prolonged monitoring group compared with the repeat 24-hour Holter monitoring group (18% vs. 10%; P=.01).

Gladstone and colleagues concluded that one or two Holter monitors following a cryptogenic stroke or TIA is not enough to exclude paroxysmal AF; prolonged monitoring for 30 days is significantly more effective for AF detection and may identify patients who could benefit from anticoagulant therapy for secondary stroke prevention.

“With about one in four strokes worldwide classified as cryptogenic, this study suggests that occult AF may underlie a greater proportion of cryptogenic strokes than previously thought,” Gladstone said.

For more information:

Gladstone DJ. LB5. Presented at: International Stroke Conference 2013; Feb. 5-8, 2013; Honolulu.

Disclosure: The trial was funded by the Canadian Stroke Network. Gladstone reports no relevant financial disclosures.