By Vincent Gerber, DVM, PhD, Dipl. ACVIM, ECEIM, WEVA Treasurer

In general, athletes tend to be healthier than nonathletic individuals. However, elite athletes—including horses—have their own subset of medical problems, which include sudden cardiac death. Sudden cardiac death in horses is often due to malignant arrhythmias that develop during exercise.

Recent studies have shown that horses can develop certain types of arrhythmias occasionally, or even normally, while they exercise, often without consequence. However, some types of arrhythmias can be life-threatening, and sudden cardiac death or collapse sometimes occurs in horses competing in equestrian sports. Currently, the limits between acceptable and potentially dangerous arrhythmias are unclear.

To better define the risks related to certain types of arrhythmias during exercise, a research group at the University of Bern, in Switzerland, is investigating cardiac adaptations to training in three-day event and endurance horses. The research team is performing complete cardiac examinations—including electrocardiograms during exercise—in competing and noncompeting sport horses to determine if training has an effect on arrhythmia occurrence and if elite athletes are at a higher risk compared to horses that perform lower levels of exercise. The veterinarians are working with a dedicated group of riders to gain knowledge that will help protect horses’ health, riders’ safety, and the public perception of equine welfare during competitions.

Cris Navas, LV, PhD, Dipl. ACVIM, the principal investigator leading these projects, will be givin