Prolonged ECG with a novel recorder utilizing electrode belt and mobile device in patients with recent embolic stroke of undetermined source: A pilot study.

BACKGROUND Paroxysmal atrial fibrillation (pAF) is a major risk factor for ischemic stroke, but challenging to detect with routine short-term monitoring methods. In this pilot study, we present a novel method for prolonged ECG and screening for pAF in patients with a recent embolic stroke of unknown source (ESUS). METHODS Fifteen patients aged ≥ 50 years with a recent ESUS were assigned to wear an external electrode belt-based 1-lead ECG device (Beat2Phone) continuously for 2 weeks (wear time). The device was operated via a mobile phone application in nonhospital conditions. The primary outcome was patient adherence to monitoring. Secondary outcomes were incidence of new pAF, quality-wise comparison to Holter, and usability of the novel ECG monitoring method with Systems Usability Scale (SUS). We also performed a 24- to 48-hr comparison between simultaneous Beat2Phone ECG and a standard Holter in 6 patients. RESULTS Wear time of Beat2Phone device was over 80% in 5 (33.3%) patients, 50%-80% in 7 (46.6%) patients, and less than 50% in 3 (20%) patients. We detected pAF ≥ 30 s in 1 patient (6.7%). In the simultaneous monitoring with Beat2Phone and Holter, there were a total of 817 (out of 1979) analyzable periods of sinus rhythm or premature atrial or ventricular beats (Cohen's Kappa coefficient 0.92 ± 0.02 between Beat2Phone and Holter), and no pAF events. Beat2Phone ECG showed remarkable SUS scores in user evaluations (average score: 81.4 out of 100 on SUS). CONCLUSIONS Beat2Phone device was easy to use among ESUS patients and in optimal conditions provided high-quality 1-lead ECG signal for diagnosing pAF. CLINICAL TRIAL REGISTRATION The study was not registered, as it was a nonrandomized single-arm pilot study.