Accuracy of a heart rate monitor for calculating heart rate variability parameters in exercising horses.

The study aims to determine how accurately a heart rate monitor (HRM) can measure heart rate variability (HRV) – a parameter that is commonly assessed for health, fitness, and scientific research purposes in horses – as compared to the traditionally used electrocardiograms (ECG).

Introduction

• The researchers begin by explaining the relevance of monitoring heart rate in horses, which is useful in assessing the animal’s fitness to exercise. Traditionally, this has been achieved through the use of heart rate monitors (HRM) or telemetric electrocardiograms (ECG).
• ECGs are often more expensive and require user experience, while HRMs are relatively cheaper and user-friendly, making them a preferred option for horse owners.
• The study focuses on heart rate variability (HRV), a metric that has been gaining attention in both research and clinical practice. HRV is typically calculated from interbeat intervals (IBI) which are obtained through ECG.

Aim and Methodology

• The goal of the study was to evaluate how accurately an HRM could assess IBI, and thereby calculate HRV. This investigation was done on both resting and exercising horses.
• A total of 13 horses and ponies under normal training conditions were included in this study. For each, simultaneous ECG and HRM recordings of at least 45 minutes were made.
• The IBI data collected from the ECG were corrected using specialized software, while the IBI recorded by the HRM were not corrected. Two parameters of HRV, the standard deviation of R-R intervals (SDRR) and the root mean square of successive differences (RMSSD), were calculated from both the ECG and HRM recordings.
• The researchers then compared the results obtained from the HRM and ECG, using statistical methods such as Bland-Altman plots and Lin’s correlation coefficient.

Results and Conclusion

• The findings showed that the mean differences between the HRM and ECG systems in evaluating HRV parameters during both resting and exercise periods was less than 0.47 ms. Further, they correlated strongly, with a correlation coefficient of over 0.999.
• Different height, weight, and body condition score had no significant effect on the results, validating the consistency of the HRM’s performance.
• The study concludes that the HRM could be a valuable easy-to-use tool for obtaining HRV parameters in both resting and active horses.