Early post-ablation rhythm monitoring using smartphone-based PPG: a real-world comparison of RFA and PFA

Background

Early recurrence of atrial tachyarrhythmia (ERAT) is common after atrial fibrillation (AF) ablation and contributes to patient symptom burden. Rhythm monitoring during the early post-ablation period is essential but often underused due to limited duration and cost of conventional ECG-based methods. Smartphone-based photoplethysmography (PPG) enables convenient, scalable, and accurate rhythm surveillance, which could allow evaluation of ablation techniques in real-world settings.

Purpose

To assess ERAT rates and time-based AF metrics early after AF ablation and compare outcomes between pulsed field ablation (PFA) and radiofrequency ablation (RFA) using smartphone-based PPG monitoring.

Methods

This retrospective single-center cohort included all patients undergoing AF ablation after implementation of a novel rhythm monitoring strategy (September 1, 2024). Patients were instructed to perform twice-daily and symptom-triggered PPG measurements, reviewed daily by an arrhythmia nurse. AF load (percentage of time in AF) and SMURDEN (number of days with at least one AF measurement) were used as time-based metrics. Data were extracted on July 15, 2025.

Results

Of 789 patients who underwent AF ablation, 511 (64.8%) were offered smartphone-based PPG monitoring, of whom 349 (68.3%) recorded at least one high-quality measurement. ERAT was detected in 110 patients (31.5%) within 8 weeks, with a median time to detection of 9.5 days (IQR 4-21.3). Median AF load was 3.7% (IQR 1.2-23.9%), median SMURDEN was 3 days (IQR 1-11), and 60 patients (54.5%) had symptomatic recurrences.

Among the monitored cohort, 160 underwent PFA and 189 RFA. In a multivariable Cox regression model with multiple imputation, PFA was independently associated with a lower ERAT risk (HR = 0.37, 95% CI 0.24-0.57, p <0.001). Persistent AF increased risk (HR = 2.08, 95% CI 1.36-3.19, p <0.001), while baseline anti-arrhythmic drug use was protective (HR = 0.57, 95% CI 0.38-0.85, p = 0.006). Results were consistent in both imputed and complete-case analyses. After applying a 4-week blanking period (65 events), PFA remained associated with a lower ERAT risk (HR = 0.21, 95% CI 0.11-0.44, p < 0.001). In patients with ERAT, RFA was linked to higher AF load (rate ratio = 2.2, 95% CI 1.17-4.16, p = 0.015) and SMURDEN (rate ratio = 2.36, 95% CI 1.37-4.05, p = 0.002) compared with PFA, after adjusting for baseline variables and confounders.

Conclusions

Smartphone-based PPG monitoring enables timely detection of atrial arrhythmia recurrence and supports time-based AF assessment during early post-ablation follow-up. In this real-world cohort, PFA was associated with lower ERAT rate and burden compared with RFA in the first 8 weeks after ablation. These results illustrate the potential of smartphone-based PPG for scalable, real-world evaluation of AF ablation techniques.Freedom from recurrence of ERAT