Validation of an equine fitness tracker: ECG quality and arrhythmia detection

Abstract

Background: Cardiac arrhythmias in exercising horses are the focus of much interest, both in terms of what is considered normal and potential associations with poor performance and sudden cardiac death. One barrier to performing large-scale studies is the lack of an easily applicable device, to allow recording of large numbers of highquality exercising electrocardiograms (ECGs). The Equimetre TM is a new wearable device, which records a single lead ECG, among other parameters. Validation of such wearable devices is essential before further studies are undertaken. Objectives:To evaluate the quality of ECG using the Equimetre TM and compare arrhythmia detection during exercise with the reference Televet TM system. Study design:Prospective blinded clinical study.Methods: Simultaneous ECGs were recorded with both systems in 49 healthy horses during exercise. High-intensity exercise (>40 km/h) was performed by 29 racehorses, and lower-intensity exercise for the remainder of the racehorses and show jumpers.Tracings were excluded if >10% artefact was present (duration of artefact relative to duration of exercise). For included ECGs, the duration of artefact was recorded and compared. ECGs were evaluated using Kubios premium software. Arrhythmia detection (yes/no) and arrhythmia classification (sinus arrhythmia, narrow complex of similar morphology to the sinus complexes or wide complex with a different morphology) were compared using Cohen's Kappa coefficient.Results: Nine Televet TM ECGs and 3 Equimetre TM ECGs were excluded due to artefact >10%. Televet TM ECGs included significantly more artefact during exercise than Equimetre TM ECGs (5% vs. 0.25% P < .001). Arrhythmia analysis was performed on 38 horses' paired ECGs. The kappa coefficient was excellent for arrhythmia detection (K = 0.97) and arrhythmia classification (K = 0.93). Main limitations:Relatively low numbers of horses with arrhythmias (n = 21) were included. The ECG recordings only provided one lead, making arrhythmia classification challenging in some cases.

Does sex of the jockey influence racehorse physiology and performance

“…The device was fitted prior to training by persons accustomed to the device. An electrode was fastened at the girth and the second secured under the saddle pad in the natural dip of the back, as previously described [41,42]. The fitness tracker recorded physiological and locomotory parameters during designated periods of trot, canter and gallop.…”

Implantable loop recorders for detecting arrhythmia in horses: Research tool or diagnostic technique?

“…Although the device cannot be applied during exercise, smartphone ECG recordings can be used as a diagnostic technique during the immediate post‐exercise period and allow a definite diagnosis of AF. Another option could be the use of equine fitness trackers which record a single lead ECG in addition to other parameters such as heart rate (Ter Woort et al, 2023). However, these wearable devices are not suitable for long‐term monitoring at rest.…”

Science in brief: The Dorothy Havemeyer International Workshop on poor performance in horses: Recent advances in technology to improve monitoring and quantification

“…Methods to obtain ECG at rest and during exercise were also explored and discussed. Dr Fe ter Woort 6 presented data showing that ECGs obtained using a fitness tracker had less artefact during exercise than another widely used ECG device. ECGs obtained with the fitness tracker had the limitation of displaying only one lead and they were not obtained at racing speed.…”

“…Methods to obtain ECG at rest and during exercise were also explored and discussed. Dr Fe ter Woort 6 and represent a large percentage of exercise-associated deaths. 7,8 In this context and expanding to many other aspects of the exercising horse the creation of shared or opensource databases was discussed.…”