Enhanced Detection and Prompt Diagnosis of Atrial Fibrillation Using Apple Watch: A Randomized Controlled Trial

Abstract

Background: Atrial fibrillation (AF), the most common cardiac arrhythmia, is a major cause of stroke and often remains undiagnosed due to its paroxysmal and frequently asymptomatic nature. Wearables provide a scalable, noninvasive screening tool.

Objectives: This trial evaluated new onset AF detection in patients at elevated stroke risk using remote smartwatch-based screening.

Methods: This prospective multicenter randomized controlled trial included patients ≥65 years with elevated stroke risk (CHA₂DS₂-VASc ≥2 men, ≥3 women) from 2 secondary care centers in the Netherlands. Patients were randomized to 6-month (180-day) monitoring with a smartwatch with photoplethysmography and single-lead electrocardiogram (ECG) functions, or standard care. ECGs were reviewed remotely by an independent eHealth team within 24 hours. The primary outcome was new onset AF, defined as a confirmed episode lasting ≥30 seconds on single-lead ECG or standard ECG methods.

Results: Between November 2022 and December 2023, 437 patients were randomized (219 intervention, 218 control); the median age was 75 years, 46.7% were female and the median CHA₂DS₂-VASc score was 3.0. New onset AF occurred in 21 (9.6%) patients of the intervention group and 5 (2.3%) patients of the control group (risk difference: 7.3 percentage points; 95% CI: 2.9-11.7 percentage points; P = 0.001; HR: 4.40; 95% CI: 1.66-11.66). Several asymptomatic AF episodes were detected only in the intervention group, while paroxysmal AF occurred in both groups.

Conclusions: This randomized controlled trial provides evidence that 6-month smartwatch-based AF screening enhances the detection rate of new onset AF compared with standard care in patients at elevated stroke risk. (Detection and Quantification of Atrial Fibrillation in High-risk Patients Using a Smartwatch Wearable [Apple Watch] [EQUAL]; NCT05686330).

Keywords: atrial fibrillation; digital health; randomized controlled trial; remote monitoring; wearable technology.