PPG-Based Smartphone Application Versus Usual Care for Atrial Fibrillation Screening: A European Multicenter Randomized Trial

Atrial fibrillation (AF) is the most frequent arrhythmia worldwide and a major cause of ischemic stroke. Screening tools are becoming increasingly popular to detect AF for stroke prevention, yet data from randomized trials is lacking. To analyze AF detection rates using a smartphone application with early intervention compared to no intervention (Sham group). This is an international, multicenter, prospective, randomized, sham-controlled, double-blinded trial between October 2019 and May 2024. Patients with no prior AF were 1:1 randomized to an intervention-group and a sham-group. The study app utilized the smartphone camera to generate photoplethysmography signals. If an arrhythmia was detected, patients of the intervention group received a notification and a 7-day patch ECG to confirm AF. 1021 patients in eight centers were randomized. Mean CHA2DS2VASc was 3.4 (±0.92) in the Intervention-group and 3.5 (±1.02) for the Sham-group. Arrhythmia was detected in 32 cases, 20 in the intervention-group and 12 in the Sham-group. AF was diagnosed in 13 patients. AF detection rates were numerically higher in the intervention-group (1.9% vs. 0.5%, p=0.094), especially in cases of asymptomatic AF (0.8% vs. 0, p=0.13). There was no difference in the rates of stroke, transitory ischemic attacks (TIA) or systemic embolisms after 6 months. In this multicenter trial, app usage in combination with early intervention did not significantly increase overall detection rates. However, asymptomatic AF detection was numerically higher in the intervention-group, aligning with current guidelines that recommend PPG-based devices for AF screening.