Understanding Mitral Valve Disease in Horses

SUMMARY: Researchers will look for biomarkers to improve diagnosis, provide a more accurate prognosis, and unravel the pathophysiology of mitral valve regurgitation in horses.

THE PROBLEM: Mitral valve regurgitation (MR) affects large numbers of athletic horses. In this disease, the heart valve does not close properly. This causes blood to flow backward to the lungs. Many horses with mild MR perform well and remain healthy. However, some horses develop severe MR. This may lead to heart failure or irregular heart rhythms. Predicting which horses will have serious issues is very difficult. This is why MR is concerning to horse owners and veterinarians.

THE PROJECT: The first goal of this study is to evaluate heart function in horses with MR. The team will use cardiac ultrasound and blood tests for heart biomarkers. The study will assess heart function and biomarkers in 70 healthy horses and 210 horses with MR. Horses with mild to moderate MR are expected to maintain normal cardiac function. They should have normal levels of cardiac biomarkers. Horses with severe MR are expected to show worsening of heart function and increased biomarkers.

The second goal is to improve the prediction of outcomes on long term. The team will perform repeat exams of horses diagnosed with MR over the past years. They aim to find reliable measures that predict how MR will progress. This will be helpful to better assess and manage these horses.

The third and final goal is to improve understanding of the disease mechanism. The researchers will explore the role of serotonin and magnesium in MR. They hypothesize that high serotonin levels and low magnesium levels result in valve disease.

POTENTIAL IMPACT: The overall aim is to improve the diagnosis and provide a more precise prognosis for MR. A better understanding of this disease in horses could improve the health and well-being of not only sports horses but all horses.

Projected End Date: 10/31/2026