The Yield of External Loop Recorder Compared to Pulse Palpation and ECG Rhythm to Detect Asymptomatic Atrial Fibrillation in a Community-Based Population

Abstract

Abstract Background and Purpose: Atrial fibrillation (AF) is one of the most common cardiac arrhythmia in the general population, and the most frequent source of cardiac emboli in patients with ischemic stroke.! The majority of AF events are underdiagnosed, as they are often asymptomatic or intermittent, and may not be detected by standard 12-lead electrocardiogram (ECG) or Holter monitor.! We have evaluated the diagnostic yield of a 21-day External-Loop Recorder (ELR) to detect AF events compared to pulse palpation and baseline ECG rhythm.!! Methods:!We enrolled 48 participants, 65 years of age or older with no history of atrial fibrillation, stroke or transient ischemic attack from three retirement/assisted facilities and one community clinic in Edmonton. The primary outcome was to detect any AF event (≥ 3 seconds) during the monitoring period. Results: The median ELR monitoring duration was 19 days (range 1-22 days) resulting in an AF detection rate of 27% (13/48), of which 77% (10/13) were < 30 seconds. Paroxysmal atrial tachycardia (PAT) was detected in 50% (24/48) of the participants. Pulse palpation was irregular in 3 participants and only 15% (2/13) of the participants with positive ELR results had irregular pulse palpation (p = 0.01). ECG baseline rhythm detected non-sinus rhythm in 6 participants, of which only 3 (50%) had AF events detected by the ELR. Conclusion: There is a significantly high rate of asymptomatic AF (mostly < 30 seconds) detected by the ELR compared to pulse palpation in the community population. The use of external loop recorders to evaluate for AF or PAF may be considered in patients at high risk for stroke.!