The use of electrocardiographic recording with Holter monitoring during treadmill exercise to evaluate cardiac arrhythmias in racehorses.

The research examines the use of Holter monitoring combined with treadmill exercise to better understand and diagnose cardiac arrhythmias in racehorses. This technology provides a comprehensive view of the horse’s heart function over an extended period, capturing potential irregularities during strenuous exercise.

Study Overview

The research takes into account the importance of performance in equine sports medicine and emphasizes the role of diagnostic tools in detecting abnormalities. Given the direct impact of cardiac arrhythmias on athletic performance, it is vital to detect and analyze rhythm disturbances during exercise. Despite arrhythmias not being present in resting conditions, they might show during maximal exercise and vice versa. Hence, this study uses Holter monitoring – a common method in human medicine recently proposed for equine patients – alongside exercise to record cardiac activity in horses for 24 hours.

• The study’s key purpose is describing the methodology used by the Department of Veterinary Clinical Sciences at the University of Milan for recording electrocardiogram (ECG) via Holter monitoring during a treadmill exercise test on standardbred racehorses.

Materials and Methods

The research uses disposable contact electrodes and a bipolar lead system for Holter monitoring. To prepare the horses, alcohol or ether is used to clean the skin, and the electrodes are moistened with gel. The monitoring device is then connected and checked for quality.

• The usual exercise routine for the horses is carried out on a high-speed treadmill with a standardised protocol. This protocol includes warm-ups, increasing speed steps, and a recovery period.
• The monitoring device operates for 15 minutes before the exercise starts and 30 minutes after it concludes.
• The collected data is then analyzed and interpreted both by a computer program and manually.

Discussion and Potential Implications

The procedure for applying monitors is well received by horses, and a high-quality ECG is recorded. Although the study doesn’t shave the horses underneath the electrode application areas, the recording quality remains satisfactory both at rest and during exercise.

• Using two bipolar leads enhances the chances of a complete recording, important during exhaustive exercise when a horse may sweat excessively, potentially hampering electrode adhesion to the skin.
• The team acknowledges that while ECG recordings are good quality, software settings intended for human medicine demand manual examination for appropriate cardiac rhythm evaluation and to prevent misdiagnoses.