Table 3. Comparison of 4 different dynamic ECG monitoring devices.

Name of device	H3-ECG	Apple Watch with KardiaBand	Multi-lead Holter	Implantable loop recorder
H3-ECG and Apple Watch with KardiaBand are remote multi-lead and single-lead wearable ECG monitoring devices, Holter is a traditional multi-lead ECG monitoring device, and implantable loop recorder is an invasive single-lead ECG monitoring device. Their respective features, pros and cons of are compared in the figure. AF: atrial fibrillation; CFDA: China Food and Drug Administration; FDA: Food and Drug Administration; ESUS: embolic stroke of undetermined source.
ECG lead	Six extremity leads (Ⅰ, Ⅱ, Ⅲ, aVR, aVL, aVF)	Lead Ⅰ	Three precordial leads (V1,V3,V5) or simulate 12 leads	Single lead
Recording method	Four short lead wires and a built-in recording ECG box.	Place thumb on the sensor to record rhythm.	7–10 long lead wires with an external recording device	Subcutaneous implantation
Advantage	Long-time (72 hours) and cardiac events recording. Remote and real-time. Close to the heart, large signal amplitude, strong anti-interference ability.	Single cardiac events recording. Far from the heart, small signal amplitude, weak anti-interference ability.	24-hour recording. Technically simple procedure and accurate detection.	Long-time recording (months or years). Remote monitoring.
Certification	CFDA	FDA	FDA	FDA
Disadvantage	Not easy to wear. Lack of clinical application research evidence.	Wave amplitude affected by pressing pressure, unable to detect continuously, large interference only detected lead Ⅰ.	Cumbersome, inconvenient. No remote real-time data. More than one day recording requires replacement of electrodes and batteries.	High costs. Invasive examination, increase the risk of infection and bleeding.
Applicable people and accuracy	Paroxysmal palpitations and asymptomatic AF. The detection of AF has a sensitivity of 94% and specificity of 98%.	Real-time monitoring of patients with paroxysmal palpitations. The detection of AF has a sensitivity of 93% and specificity of 84%.	Non-real-time 24-hour monitoring of patients with paroxysmal palpitations. The detection of AF has a sensitivity of 91% and specificity of 99%.	Unexplained syncope, asymptomatic AF. AF can be documented in approximately 25% of patients with the diagnosis of ESUS.