Remote Monitoring of AF Recurrence using mHealth Technology (REMOTE-AF)

Abstract

This proof-of-concept study sought to evaluate changes in heart rate (HR) obtained from a consumer wearable device and compare against implanted loop recorder (ILR)-detected recurrence of atrial fibrillation (AF) and atrial tachycardia (AT) after AF ablation. REMOTE-AF (NCT05037136) was a prospectively designed sub study of the CASA-AF randomised controlled trial (NCT04280042). Participants without a permanent pacemaker had an implantable loop recorder (ILR) implanted at their index ablation procedure for longstanding persistent atrial fibrillation. HR and step count were continuously monitored using photoplethysmography (PPG) from a commercially available wrist-worn wearable. PPG recorded HR data was pre-processed with noise filtration and episodes at 1-minute intervals over 30 minutes of heart rate elevations (Z-score = 2) were compared to corresponding ILR data. Thirty-five patients were enrolled, with mean age 70.3 +/- 6.8 yrs and median follow-up 10 months (IQR 8-12 months). ILR analysis revealed seventeen out of thirty-five patients (49%) had recurrence of AF/AT. Compared with ILR recurrence, wearable-derived elevations in HR ≥ 110 beats per minute had a sensitivity of 95.3%, specificity 54.1%, positive predictive value (PPV) 15.8%, negative predictive value (NPV) 99.2% and overall accuracy 57.4%. With PPG recorded HR elevation spikes (non-exercise related), the sensitivity was 87.5%, specificity 62.2%, PPV 39.2%, NPV 92.3% and overall accuracy 64.0% in the entire patient cohort. In the AF/AT recurrence only group, sensitivity was 87.6%, specificity 68.3%, PPV 53.6%, NPV 93.0% and overall accuracy 75.0%. Consumer wearable devices have the potential to contribute to arrhythmia detection after AF ablation.