Smartwatches have been gaining popularity, and smartwatch-based patient-activated recordings have been widely used for screening atrial fibrillation (AF) and sleep-disordered breathing. We encountered a 79-year-old man who routinely activated a smartwatch ECG in the morning. He had documented paroxysms of AF while working as a businessman a decade ago. Thereafter, the paroxysms were not documented after he retired from work; therefore, pulsed field ablation was deferred. However, the smartwatch repeatedly detected AF paroxysms the following morning, only after the smartwatch had issued a breathing-disturbance notification during sleep. Smartwatch ECG cannot completely substitute for conventional ECG, and smartwatch-detected breathing disturbance is not equivalent to polysomnography (PSG)-detected obstructive sleep apnea (OSA). However, this case suggests that nocturnal respiratory disturbance may be associated with daily AF paroxysms and that this possibility may be detected using a single smartwatch. Accumulation of similar cases with simultaneous polysomnographic and ECG monitoring may help clarify the mechanistic relationship between nocturnal hypoxemia and AF paroxysms.
Maruyama et al. (Tue,) studied this question.