These tools have many uses but are not without their limitations. Learn the ins and outs of heart rate monitors so you can make the best decision for your horse.

If you have never used an equine heart rate monitor (HRM), you could be missing out on essential information about your horse and her heart. Understanding more about them, and what they can and can’t do, is the best way to optimize their use.

Your horse’s heart

Hickstead was a champion jumper whose sudden death in 2011 from an aortic rupture¹ had equestrians concerned about their horses’ hearts. But the equine heart bears little similarity to the human heart and its conditions.

Horses do not live as long as we do (horses live 20 to 25 years, humans up to 85 years). The equine diet tends to be cleaner than ours, with fewer chemicals and preservatives. In addition, horses eat few to no fats (they’re the only mammal without a gallbladder, and can be considered super-vegans). So horses bypass common long-term diseases often found in humans.

Heart failure is relatively uncommon in horses. To say that a horse died of a heart attack is making a generic statement, since the most common heart-related death in equines is caused by an aortic rupture that leads to heart failure (Hickstead’s diagnosis).

Heart conditions in horses

Equine hearts are highly effective organs. Horses rarely suffer coronary artery disease, and heart attacks are rare.

Heart issues in horses range from having no significance, to mildly limiting, to life-threatening. Disease can develop rapidly (acute) or slowly (chronic). Very few horses have problems, but tests can determine extremely variable underlying causes. History is always part of diagnosing heart disease, but there is still much to learn about the equine heart.

Normal hearts beat evenly, although murmurs and arrhythmias (irregular heartbeats) are common. Congenital anomalies remain infrequent. The most common heart condition affecting performance is atrial fibrillation, in which the upper chambers can beat up to 400 bpm. Swale (sudden death syndrome) is more prevalent in race horses.

Other contributing factors that can damage the equine heart include trauma, congenital malformation, toxic insult, neoplasia, degeneration, inflammation, lesions, infection, fever, anorexia, low body score, vessel laceration, vitamin toxicity and bacteria colonization, or disease in other organs. Calming agents and various drugs can alter the heartbeat.

Call your vet if you detect a weak rapid pulse or erratic, unstable and/or muffled heart sounds.

What is an equine heart rate monitor?

An equine heart rate monitor (HRM) is a device that monitors your horse’s heart during exercise. They range from simple minimal buttons to extravagant GPS systems, and come in hand-held, girth belt and electrode models, all equipped with an electronic training record. They give riders a scientific look at their horses.

HRMs reference the ups and downs of a horse as you work him, and are valuable when used to chart him through strenuous training.

GPS systems with sophisticated performance indicators store information that can be downloaded to your computer for complete high-resolution analysis of the training session.

Prices: A stethoscope costs around $250. A basic HRM runs from $150 to $250, while a device with all the bells and whistles can cost up to $500.

HRM uses and advantages

The use of heart rate monitors is typically specific to conditioning, mostly for racing, eventing, endurance, dressage, treadmills and in conditioning/medical facilities.

• HRMs take the guesswork out of whether or not you are putting too much stress on your horse. They help avoid physical wear and tear, inform you of training plateaus, and help tailor programs such as interval training, altitude or swimming. HRM information is indisputable, avoids assumptions, and is a valuable tool for conditioning.
• When horses act out, they are often diagnosed as “bad” or “spoiled” when, in reality, they could be in pain. However, heart rates can spike during movements such as gait and directional changes, signaling pain or injury. Use of a monitor alerts you to these spikes, thereby preventing your horse from further suffering.
• HRMs can monitor emotional states such as excitement, fear or anxiety, and help solve issues in jumping performance (e.g. sudden refusals or rushing).
• They signal early lameness, colic and depression, declines in performance, and changes in fitness.
• Monitors are invaluable for tracking recovery and physical improvements, and changes in therapy (massage, chiropractic).
• HRMs allow you to track the effects of weather extremes, especially heat, and changing terrain, which quickly trigger higher bpm (beats per minute).
• Non-performance horses (light pleasure) can also take advantage of an HRM, as can foals (from birth), especially if they are bred to achieve high levels of performance.

Other uses

• Good for pre-purchase exams.
• An HRM can be used by a veterinarian to diagnose a heart flutter. Not all flutters are life-threatening.
• These devices can uncover the effects of poor body condition. During heavier states of conditioning (endurance, eventing, polo, cutting), often the horse is pushed from anaerobic threshold to anaerobic metabolism, which uses carbohydrates for fast energy, minus the use of oxygen. This produces lactic acid in the muscles and pushes the heart threshold over 160. Pushing the heart rate of an unconditioned horse over 160 too often could lead to heart trauma. Wearing a heart monitor at these times can show the rider instantly where harm may be occurring by indicating that threshold before damage occurs. In addition, honest horses (that give their all when asked) may hide the internal effects of intermittent heavy use, but a heart monitor can assess the situation quickly, especially in heart trauma.

HRM limitations

It is important to remember that heart rate monitors are a tool. It does not take the place of learning all you can about health issues and conditioning; your horse’s legs, skeleton and mental capacity must also be taken into account during training.

An HRM is not used to monitor speed, nor is it a tachometer.

These devices are not advisable for horses with heart murmurs, as they are incapable of specifically locating and recording the murmur, and could bypass vital health information.

As with any device, equine heart monitors are only as useful as the person using them. Knowing what a heart rate monitor is most effective for is vital for getting the most out of it.

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¹en.wikipedia.org/wiki/Hickstead_(horse)