Effectiveness of photoplethysmography-based rhythm monitoring after atrial fibrillation ablation using a smartphone application

Abstract

Abstract Introduction Recurrence of atrial fibrillation (AF) after AF ablation is frequent. Monitoring recurrence is essential for attributing patient symptoms and for assessing both AF burden and treatment effectiveness. The conventional approach relies on periodic (long-term) electrocardiograms (ECG) and is constrained by limited monitoring time, measurement dispersion, and cost. Furthermore, patients are unable to prioritize measurements based on symptoms. Photoplethysmography (PPG) emerges as a technology that could potentially transform any smartphone into a rhythm monitoring device, thereby mitigating the limitations associated with current practices. Selected applications leveraging this technology have demonstrated excellent usability and accuracy for the detection of AF. However, the effectiveness of PPG-based follow-up remains uncertain. Purpose To compare the effectiveness of digital follow-up utilizing a PPG-based smartphone application with conventional ECG-based follow-up for the detection of atrial arrhythmia recurrence after ablation. Methods Patients undergoing AF ablation were consecutively enrolled and monitored using a 24h-ECG at 3-6-12 months on top of ECGs conducted for clinical indications (conventional follow-up). Additionally, patients were instructed to perform PPG measurements twice daily or whenever symptoms were perceived, over the course of one year (digital follow-up). The primary outcome was recurrence of atrial arrhythmia. Results In total, 96 patients (69% male, mean age 64 [58 – 68] years) performed 39,895 PPG measurements. The compliance rate (n performed/prescribed) was 92.6% for ECG and 78.2% for PPG recordings. After one year follow-up, atrial arrhythmia recurrence was detected by conventional follow-up in 17.9% and in 38.5% of patients by digital follow-up (odds ratio, 3.4; 95% CI: 1.7-7.1). The confidence interval lower limit exceeded the predefined non-inferiority margin (p for non-inferiority > 0.001). Hence, superiority was tested (p for superiority = 0.001). The negative predictive value of digital follow-up for atrial arrhythmia detected with conventional follow-up was 98.3% (95% CI: 90.1-99.9%). Symptoms were reported in 81.1% of PPG-detected atrial arrhythmias and episodes sustained for 3.9 [1.1 – 22.7] hours. Conclusions Among patients with AF ablation, digital PPG-based rhythm monitoring with a smartphone, was non-inferior in the detection of atrial arrhythmia recurrence after ablation. Moreover, the detection of atrial arrhythmia was significantly increased compared to conventional ECG-based monitoring.