A dog’s heart is a nonstop machine that beats in a tightly controlled rhythm to circulate blood throughout the body. Heart rate is defined as the number of times the heart beats per minute.

Many conditions can disrupt a dog’s normal heart rate, causing organs not to get the vital blood they need to function properly. That’s not something to take lightly. An abnormal heart rate often signals the need for veterinary care and attention.

What constitutes an abnormal heart rate in dogs? What can you do about it? Can cardiovascular nutritional supplements promote a normal dog heart rate? We’ll answer these questions and more so you can help keep your dog’s heart (and heart rate) going strong.

Why Understanding a Dog’s Heart Rate Matters

Knowing your dog’s normal heart rate will help you and your veterinarian quickly recognize when the rate is abnormal.

A normal dog heart rate is also known as the resting heart rate, the rate at which the heart beats when the body is at rest (like when you’re sitting still at the doctor’s office while a nurse takes your heart rate).

Regularly monitoring your dog’s resting heart rate will give you an accurate estimate of what’s normal. No need to buy a stethoscope, though. Later in the article, we’ll explain how to measure your dog’s heart rate without special equipment.

Also, you don’t have to check your dog’s heart rate every week. A dog’s resting heart rate stays steady over time. An occasional check at home and heart rate checks at each veterinary appointment are sufficient for the average, healthy dog.

Changes in heart rate can signal an underlying health issue that needs attention. Other times, though, a change in heart rate is normal and temporary, such as an increased heart rate with exercise. Your veterinarian can help you determine whether a change in heart rate is normal or indicates an actual health problem.

What Is a Normal Dog Heart Rate?

A dog’s normal heart rate primarily depends on their size and age. Normal heart rates are generally higher in puppies and small dogs than in adult dogs and large dogs.

Here’s a chart of average heart rates in dogs, measured in beats per minute (BPM):

Type of Dog	Normal Heart Rate (BPM)	Abnormally Slow Heart Rate (BPM)	Abnormally Fast Heart Rate (BPM)
Puppy	160 to 220	Less than 160	Greater than 220
Small Adult Dog	100 to 140	Less than 80 to 100	Greater than 140-180
Large Adult Dog	60 to 100	Less than 60	Greater than 100-140

An abnormally slow heart rate is called bradycardia, while an abnormally fast heart rate is called tachycardia.

Abnormal Heart Rates in Dogs

Abnormal heart rates in dogs are either physiologic (normal and temporary) or pathologic (caused by an underlying health issue).

Bradycardia occurs when the heart beats too slowly. Here are some causes of bradycardia in dogs:

Physiologic

• Very athletic dog

Pathologic

• Liver or kidney failure
• Hypokalemia (low potassium levels)
• Myocarditis (heart muscle inflammation)
• Hypothyroidism (underactive thyroid gland)

Tachycardia occurs when the heart beats too quickly. A rapid heartbeat doesn’t allow the heart’s chambers to fully refill with blood between contractions (when the heart ‘squeezes’). Here are common causes of tachycardia in dogs:

Physiologic

• Stress
• Exercise
• Anxiety
• Excitement

Pathologic

• Fever
• Shock
• Infection
• Dehydration
• Low blood pressure
• Congestive heart failure

How to Check a Dog’s Heart Rate

Check your dog’s heart rate regularly when your dog is at rest.

There are several places on your dog’s body where you can check the heart rate:

• Directly over the heart: Place your hand on the left side of the chest, behind the elbow of the left front leg.
• Inside the front of the right or left hind leg.

Even though the heart rate is reported as beats per minute (BPM), you do not have to count for 60 seconds. Instead, count the number of beats for 15 seconds, then multiply that number by four. For example, if you count 30 beats in 15 seconds, the heart rate is 120 BPM (30 x 4).

Track the time with a watch, stopwatch, or your phone’s timer. Also, take your dog’s heart rate several times to ensure your measurement is accurate. Write down the measurement, especially if it’s abnormal.

Abnormal Dog Heart Rate: Next Steps

Take your dog to your veterinarian if your dog’s heart rate is abnormal and you’re unsure why. During the appointment, tell your veterinarian what heart rate you measured at home. They will perform a physical exam and listen closely to your dog’s heart.

Your veterinarian will then perform other diagnostic tests to examine your dog’s heart. One such test is an electrocardiogram, which evaluates the heart’s electrical activity. An echocardiogram is an ultrasound that shows the heart’s structures and how the heart is beating and pumping blood. A chest X-ray may show an abnormal appearance of the heart (e.g., enlargement).

In addition, your veterinarian will perform bloodwork and a urinalysis to evaluate your dog’s overall health and look for evidence of an underlying illness.

Treating an Abnormal Heart Rate

An abnormal heart rate can lead to other health problems, so it is essential to re-establish a normal heart rate.

In cases of physiologic changes, such as exercise or anxiety, treatment may not be necessary. However, if your dog has an underlying illness, that illness will need to be treated and managed to get your dog’s heart rate back to normal.

For example, if your dog is diagnosed with congestive heart disease, a medication like Vetmedin (pimobendan) can help relax and open up coronary blood vessels, reducing the strain on the heart and stabilizing your dog’s heart rate.

Some dog breeds are predisposed to cardiovascular stress, while others may experience changes in their heart rate as they age. Ask your vet if your dog would benefit from a cardiovascular nutritional supplement to help maintain a normal heart rate. These supplements come in a variety of forms, from tasty chews to capsules, and feature natural ingredients that help support healthy cardiac function. Such as:

• Taurine – an amino acid used to treat types of heart disease in dogs caused by a taurine deficiency
• Potassium and Magnesium – help the heart muscle contract and relax
• Selenium – protects the integrity of blood vessels
• Arginine and Hawthorn berry extract – promote circulation and normal blood pressure