Dressing heart smart: an e-textile based garment for home-based ECG monitoring

Author: Meseret Nigatie Teferra

Teferra, Meseret Nigatie, 2021 Dressing heart smart: an e-textile based garment for home-based ECG monitoring, Flinders University, College of Science and Engineering

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Abstract

Cardiovascular disease (CVD) continues to be the leading cause of death and the primary reason for hospitalization worldwide. As a result, the medical system is enormously affected considering the unprecedented increment of life expectancy over previous decades. The investment in hospital infrastructure and the burden on health care facilities required to support the rapidly increasing number of patients can be minimized if centre-based cardiac rehabilitation is conducted outside of the hospital premises. Electronic-textile (e-textile)-based cardiac monitoring offers a viable option to allow cardiac rehabilitation programs to be conducted outside of the hospital.

This Ph.D. thesis presents the design, construction, and testing of a diagnostic level e-textile-based electrocardiogram (ECG) smart vest. The main findings are I) In an attempt to identify the knowledge gap and map the available evidence on e-textile based cardiac monitoring, a systematic scoping review was conducted based on a prior protocol. The systematic review concluded that the use of a 12-lead, personalized, home-based cardiac rehabilitation monitor containing fully textile-integrated electronics with diagnostic capability is yet to be reported. Therefore, there is potential for future research in this area. Additionally, motion artefact continues to be a challenge. II) A miniature ECG hardware suitable for wearable application and extended ambulatory monitoring was realized. III) A versatile, smart ECG vest that is easy to use and could be worn for seamless ambulatory monitoring was successfully implemented. The desired compression pressure applied by the smart garment for a stable-skin electrode interface was experimentally estimated. IV) The optimal electrode placement regarding the EASI configuration was studied. In this regard, placing the 'A' and 'I' electrodes on the left and right anterior axillary point respectively and the 'E' electrode slightly lower than the lower sternum (xiphoid process) showed higher signal quality compared to the standard EASI electrode placement during sideways movement, sitting/standing from a chair and climbing stairs. V) The method of connecting the textile electrodes to the smart ECG vest was examined, and it was determined that there was no significant signal quality difference between the ECG collected from the removable electrodes and the ECG from the embedded textile electrodes. However, removable textile electrodes could be swapped without affecting the integrity of the smart ECG vest while increasing its flexibility. VI) A pilot study was conducted to compare the performance of the textile-based ECG against the traditional Holter monitor. The results showed that there was no significant difference between the ECG from the textile-based electrodes in the smart vest and the reference ambulatory monitor.

The standard ambulatory monitor utilizes sticky wet-gel electrodes where the ECG quality deteriorates over time due to the drying of the gel interface. Moreover, the ECG lead wires reduced the comfort of the users. On the other hand, the proposed textile-based ECG monitor has embedded wires and textile electrodes. The smart ECG vest is easy to use and could be worn without the need for assistance to put on/off for seamless ambulatory monitoring. The intuitive design significantly reduced the time need to train the users. Therefore, the proposed textile-based EASI 12-lead equivalent ECG monitor could be a viable option for long-term real-time monitoring of cardiac activities, and a clinical trial is recommended based on a population with a known cardiac disease to validate and produce clinically significant results.

Keywords: Ambulatory cardiac monitoring, cardiac event monitor, cardiac rehabilitation, EASI ECG, electronic cloth, electronic garment, electronic-textile ECG, e-textile electrodes, fibertronics, heart rate monitor, Holter monitor, home-based monitoring, remote heart monitoring, smart ECG vest, smart fabrics, smart garment, smart monitoring, textronics, wearable sensing

Subject: Engineering thesis

Thesis type: Doctor of Philosophy
Completed: 2021
School: College of Science and Engineering
Supervisor: Professor Karen Reynolds