An Apple Watch ECG misclassified typical atrial flutter as sinus rhythm in 1 patient, highlighting that AF-validated smartwatch algorithms may miss other supraventricular arrhythmias.
Case Report (n=1)
Does a single-lead Apple Watch ECG accurately detect atrial flutter compared to a standard 12-lead ECG in a patient with palpitations?
Smartwatch algorithms validated for atrial fibrillation may misclassify other supraventricular arrhythmias, such as atrial flutter with a regular ventricular response, highlighting the need for 12-lead ECG confirmation.
Consumer wearables are increasingly used to document palpitations, but their algorithms are almost exclusively validated for atrial fibrillation (AF). We report a 70-year-old man with recurrent palpitations, no prior cardiovascular history, and controlled hypertension. A single-lead Apple Watch ECG classified sinus rhythm at 75 bpm, while a same-day 12-lead ECG revealed typical atrial flutter with sawtooth waves and regular atrioventricular conduction. After adequate anticoagulation, the patient underwent successful electrical cardioversion with 120 J and remains in stable sinus rhythm. This case highlights that AF-validated smartwatch algorithms may miss other supraventricular arrhythmias, particularly with regular ventricular response. Smartwatches can aid AF screening and symptom capture, but persistent symptoms require confirmation with standard 12-lead ECG. Future work should prioritize algorithm refinement and rigorous, post-market validation beyond AF to ensure that consumer devices transition from wellness tools to clinically reliable instruments for arrhythmia management.
Ratti et al. (Thu,) conducted a case report in atrial flutter (n=1). Apple Watch ECG vs. 12-lead ECG was evaluated on arrhythmia classification. An Apple Watch ECG misclassified typical atrial flutter as sinus rhythm in 1 patient, highlighting that AF-validated smartwatch algorithms may miss other supraventricular arrhythmias.