Mitral valve regurgitation (MR) affects a large number 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. On the other hand, 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 of important concern to horse owners, especially during prepurchase exams.
The first goal of this study is to evaluate heart function in horses with MR. We will use cardiac ultrasound and blood tests for heart biomarkers. The study will assess heart function and biomarkers in 100 healthy horses and 300 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. We will perform repeat exams of horses diagnosed with MR over the past years. We 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. We will explore the role of serotonin and magnesium. We think that high serotonin levels and low magnesium levels result in valve disease.
The overall aim is to improve the diagnosis and provide a more precise prognosis for MR. By better understanding of the disease in horses, we aim to improve the management of sports horses with this condition.