Apr 02, 2023

Equine Medical Research Final Report: Working Toward a Genetic Test for Heart Arrhythmias

RESULTS: Researchers record higher than reported incidence of atrial fibrillation in Standardbred racehorses.

Morris Animal Foundation-funded researchers from the University of Minnesota are investigating if genetic variants can help identify horses at high risk of developing potentially fatal cardiac arrhythmias. Cardiac arrhythmias are thought to be an important cause of sudden death in horses during exercise. Most horses that develop arrhythmias have no underlying structural heart disease, making it challenging to detect animals that may succumb to the condition.

Studies in human athletes with arrhythmias, but with no underlying structural heart disease, show the condition is almost exclusively caused by genetic variants. Building on this knowledge, researchers identified 36 variants in a small number of Standardbred racehorses with atrial fibrillation (an irregular heart rhythm). These variants are in genes known to cause arrhythmias in people. The team is testing if these variants are associated with arrhythmias in a larger group of Standardbred racehorses.

Early data showed that 2% of Standardbred racehorses in the study had an arrhythmia (second degree atrioventricular block or intermittent sinoatrial arrest) at rest that is considered normal in fit and healthy horses. About 5% of racehorses also had a history of or were in atrial fibrillation, which is the most common arrhythmia known to negatively affect performance. This is higher than the previously reported frequency of atrial fibrillation (0.14%) in racing Standardbreds.

DNA analysis of samples is ongoing to determine which variants are associated with cardiac arrhythmias including atrial fibrillation. If successful, the team will use this information to develop genetic tests that will become part of screening protocols to help with early identification of horses at increased risk of developing arrhythmias, with the goal of reducing sudden cardiac death in horses. Increased monitoring of horses at high risk of sudden cardiac death will improve our understanding about why certain horses die unexpectedly during and after exercise and may lead to strategies to prevent sudden cardiac death in racehorses.

Thank you, United States Eventing Association, for your generous sponsorship of this study!

May 18, 2025 Education

How to Ride the Horse You Thought You Bought

In this excerpt, trainer and educator Anne Buchannan explains bit contact connection and why it matters for true collection and healthy movement.

May 17, 2025 Education

Eventing 101: The Show Secretary is Your New Best Friend. Here’s How to Keep Them Happy

Familiarizing yourself with the key players at each horse trial is an important step to your success at your next competition. One of those important figures is the show secretary. Think of the show secretary as the mastermind behind most of the organizational efforts related to each horse trial. They manage entries, the show schedule, ride times, stabling, and so much more. Without the hard work of the show secretary and their office staff, a horse trial simply would not be able to operate.

May 16, 2025 Officials

USEA Foundation Announces the Janet Briggs Fund for the Continuing Education of Licensed Officials

The USEA Foundation is pleased to announce a new initiative, the Janet Briggs Fund for the Continuing Education of Licensed Officials. Established in memory of Janet Briggs, this fund honors her lifelong dedication to the sport of eventing by supporting the ongoing education and development of eventing licensed officials.

May 16, 2025 Eventing News

USEA Events A-Z: Hunter’s Run Farm Horse Trials

In the rolling countryside of Metamora, Michigan, there’s a place where eventers gather not just to compete, but to celebrate the spirit of the sport. Area VIII’s Hunter’s Run Farm—home to the Hunter’s Run Farm Horse Trials—has long been a beloved destination for riders across the Midwest, and this year, it’s gearing up for one of its most exciting seasons yet.

Official Corporate Sponsors of the USEA

Official Joint Therapy Treatment of the USEA

Official Feed of the USEA

Official Saddle of the USEA

Official Forage of the USEA

Official Competition & Training Apparel of the USEA

Official Horse Boot of the USEA

Official Shock Wave of the USEA

Official Horse Wear of the USEA