Heart problems are uncommon in the horse and represent a small fraction of poor performance cases. However, when cardiac problems do occur it is imperative that they are investigated to ensure the safety of the horse as a ridden athlete, as the consequence of such problems could be catastrophic for both horse and rider.

Cardiac abnormalities fall into two categories:

• irregular heart rhythms (arrhythmias); or
• abnormal heart noises (murmurs).

Both arrhythmias and murmurs can be classified as either those which are considered to be a variation of normal (physiological); or those which represent a clinical problem (pathological). Signs associated with heart disease include poor performance; tiring quickly at exercise (hitting a wall); prolonged recovery from exercise; generalised lethargy; swelling between the front legs.

The first step in cardiac evaluation is auscultation – using a stethoscope to carefully listen to the heart rate and rhythm, and identify any possible abnormalities. Based on this it is possible to characterise any abnormalities and assess whether further evaluation is required. Investigations into cardiac problems may be performed using one or more of the following techniques.

• Electrocardiography (ECG). This technique is used to assess arrhythmias and may be done whilst the horse is at rest, often over a 24hr period; and at exercise for a complete evaluation.
• Blood testing for specific cardiac markers.
• Echocardiography (heart scan). Ultrasonography of the heart is used to examine the heart structures, sizes shape and is particularly useful where heart murmurs are detected.

All of these tests may be undertaken at your yard or another appropriate site, such as Lingfield Park (exercising ECGs); or at our clinic in Felbridge. We have three RCVS Advanced Veterinary Practitioners in Equine Medicine, including a Diploma holder working at Lingfield Equine Vets; however, in particularly challenging cases we work closely with prominent equine cardiology Dr Lesley Young to your horse is provided with the very best level of care.