Introduction: Although atrial fibrillation (AF) is often preceded by increased ectopic activity, the role of triggering factors in the sequence of physiological processes is not yet understood. This study aims to explore the relation between potential triggers detected in wearable-based physiological signals and the occurrence of ectopic beats.
Methods: Week-long ECG and acceleration signals were collected during free-living activities from 165 patients with paroxysmal AF, employing an ECG patch attached to the chest. The signals were used for detecting potential triggers due to physical exertion, psychophysiological stress, lying on the left side, and sleep disturbances. Ectopic beats in acceptable-quality ECG segments were detected by analyzing beat-to-beat intervals. To assess the relation between detected potential triggers and the occurrence of ectopic beats, a measure of relational strength is used accounting for pre- and post-trigger ectopic burden. To assess relational strength unrelated to the potential trigger, a control relational strength is computed using randomly placed control triggers.
Results: For some patients, relational strength increases for all four trigger types relative to control relational strength. Overall, sleep disorders and physical exertion emerged as the most significant triggers, associated with the largest increase in relational strength across the largest number of patients, with p = 0.028 and p = 0.046, respectively. No significant difference was observed between relational strength and control relational strength for psychophysiological stress and lying on the left side.
Conclusion: Detection of potential triggers that initiate ectopic activity may become an important aspect of personalized AF management, allowing clinicians to target the underlying causes of increased ectopic activity in individual patients.