JMIR Publications

ABSTRACT

Background:

Cardiac arrhythmias are a leading cause of death. Twelve-lead electrocardiogram (ECG) is the mainstay for diagnosing arrhythmias e.g. atrial fibrillation (AF) and cardiac conduction disorders e.g. long QTc (LQTc). Handheld 12-lead ECG devices are emerging in the market. With emerging technology options to acquire an ECG in various clinical settings, evaluation of device usability should go beyond validation of the device in a controlled laboratory setting but also assess user perceptions and experience which are crucial for successful implementation in clinical practice.

Objective:

This study aimed to evaluate clinician and patient perceptions and experience regarding the usability of a handheld 12-lead ECG device compared to routinely used conventional 12-lead ECG machine.

Methods:

A mixed methods study was conducted with clinicians and patients in outpatient clinics and cardiology wards at Westmead Hospital, New South Wales, Australia. Each patient had two ECGs in two postures (supine and standing) acquired by each device in random sequence. The times taken by clinicians to acquire the first ECG (efficiency) using the devices were analysed using linear regression. ECG parameters (QT, QTc, HR, PR, QRS) and participant satisfaction survey were collected. The device reliability was assessed by evaluating the mean difference of QTc measurements within ± 15 milliseconds and intraclass correlation coefficients (ICC), and level of agreements (Kappa) of the devices in detecting AF and LQTc. Clinicians’ perceptions and feedback were assessed by semi-structured interviews drawing on the framework of the Technology Acceptance Model.

Results:

100 patients (mean 57.9y (SD 15.2y), 64% male) participated with 783 ECGs acquired, and engaging 11 clinicians (90.9% of them acquired ECGs daily or weekly). Mean difference in QTc measurements of both devices were within ± 15 milliseconds with high ICC (ranged 0.90-0.96), and the devices had a good level of agreement in diagnosing AF and LQTc (Kappa ranged 0.68 – 0.93). Regardless of device, QTc at standing was lengthened compared with QTc at supine. Clinicians’ ECG acquisition times improved with usage (p for trend <0.001). Clinicians reported that device characteristics (small size, light weight, portability and wireless ECG transmission) were highly desired features. Most clinicians agreed that the handheld device could be used for clinician-led mass screening with enhancement in efficiency by increasing user training. Generally, patients reported that they felt comfortable when they were connected to both ECG devices.

Conclusions:

The handheld 12-lead ECG device was comparable to a conventional ECG machine in its reliability and usability. The user-centered evaluation approach helped us identify remediable action to improve efficiency of using the device, identified highly desirable device features which could potentially help mass screening and remote assessment of patients, and the approach could be applied to evaluate and better understand the acceptability and applicability of new medical devices. Clinical Trial: Not applicable.