Smartphone app-based approximation of time spent with atrial fibrillation and symptoms in patients after catheter ablation: Data from the TeleCheck-AF project

BACKGROUND AND AIMS: Reduction of atrial fibrillation (AF) burden is the preferred outcome measure over categorical AF rhythm recurrence after AF ablation. In this sub-analysis of the TeleCheck-AF project we tested the feasibility of smartphone app-based approximation of time spent with AF and/or symptoms. METHODS: Patients scheduled for at least one teleconsultation during the 12-month follow-up after AF ablation were instructed to use a smartphone photoplethysmography (PPG)-based application for simultaneous symptom and rhythm monitoring 3-times daily for 1 week. Proxies of time spent with AF and/or symptoms (%-recordings, load, %-days), temporal aggregation of AF and/or symptoms (density), and symptom-rhythm correlation (SRC) were assessed. RESULTS: In total 484 patients (60% male, 62±9.9 years) were included. Adherence, motivation and patient satisfaction were high. %AF-recordings, AF load and %AF-days (rs= 0.88-0.95) and %symptom-recordings, symptom load, %symptom-days (rs= 0.95-0.98) showed positive correlations. The SRC correlated negatively with time spent with symptoms (rs=-0.65--0.90) and with time spent with AF (rs=-0.31--0.34). In patients with paroxysmal AF before ablation and AF during the monitoring period, 87% (n=39/44) had a low-density score <50% ("paroxysmal AF pattern") while 5% (n=2/44) had a high-density score >90% ("persistent AF pattern"). Corresponding numbers for patients with persistent AF before ablation were 48% (n=11/23) and 43% (n=10/23), respectively. CONCLUSIONS: On-demand, app-based simultaneous rhythm and symptom assessment provides objective proxies of time spent with AF and/or symptoms and symptom-rhythm correlation, which may assist in assessing AF and symptom outcomes after AF ablation.