<iframe src="https://www.googletagmanager.com/ns.html?id=GTM-PK9D66" height="0" width="0" style="display:none;visibility:hidden" title="gtm-frame"></iframe>Heart diseases and defects in dogs | Agria Pet Insurance
03330 30 10 00
Get a quote
My AccountGet a quote

Back to Guides and advice

Heart diseases and defects in dogs

We think a lot about our "hearts" at home, but how much do you really know about your dog's heart? What heart diseases and defects can your dog suffer from and is there anything you can do to prevent or avoid heart problems?
Heart diseases and defects in dogs

Does your dog become abnormally short of breath? Do they drink more than usual or have they suddenly started coughing? It could be a sign that your dog has suffered from a heart disease or has had a heart defect. 

A healthy heart

A dog's heart, just like a human's, consists of two chambers and two atria. The hearts job is to allow the right side to receive oxygen-poor blood from the body and send it to the lungs, and to allow the left side to receive oxygen-rich blood from the lungs and pump it out into the body.

A large, healthy, adult dog's heart beats about 70-100 beats per minute. Large and older dogs' hearts beat more slowly than smaller and younger dogs, which can beat up to 200 beats per minute. A scared and stressed dog also has a faster rate.

All dogs' hearts beat unevenly, slower when inhaling than exhaling. This is called respiratory arrhythmia.

To check the heartbeat, bend your dog's elbow joint slightly backwards and upwards, and inside you will find the heart. You'll be able to feel the strength and rhythm of the heart's beat.

The easiest place to find the pulse is in the groove along the back of the dog's belly.

Heart disease in dogs

There are several heart diseases in dogs. Approximately five to ten percent of our dogs are affected. The most common is that middle-aged and older dogs develop a murmur as a result of chronic changes to the heart's valves, so-called endocardiosis.

Another heart disease is cardiomyopathy, also called acquired heart muscle weakness, which is a change in the heart muscle. This more often affects larger dog breeds.

Some dogs can have rhythm disturbances. Then the heart beats abnormally. 

Congenital heart defects are not that common, but they can affect any breed. For example, it may be that the vessels do not close properly, the aorta may be misaligned or there may be holes between the chambers causing the blood to go the wrong way.

The most common cause of sudden unexpected death in a dog, and especially in young dogs, is some type of heart disease - often a congenital heart defect. Many heart defects are hereditary and you should therefore not breed a dog with heart problems.

Heart murmur

A heart murmur is caused by eddies in the blood passing through the heart. It can be due to malformations in vessels or heart valves, holes in the heart walls or inflammatory changes in the valves. Dogs can have wheezing without showing other symptoms for a long time. After some time, often several years, however, the heart gets tired and it cannot pump the blood around in the same way as a healthy heart. The heart expands and becomes enlarged. The blood builds up in the lungs, which leads to fluid leaking into the lungs and a pulmonary edema occurs. The result is that the dog begins to cough and finds it increasingly difficult to breathe. 

Symptoms of heart failure

Symptoms of heart failure can be that the dog shows signs of fatigue, has breathing problems and pants, coughs or has disturbances in the heart rhythm. The dog may also have a reduced appetite, become wobbly and faint. 

Treatment of heart defects

If you suspect that your dog has a heart defect, it is important to see a veterinarian to get a diagnosis. The vet can examine the heart by listening to it, looking at the EKG, x-ray and ultrasound. In many cases, timely treatment, such as special heart medications and diuretics, can make the dog feel much better.

Can heart defects be prevented?

Since heart defects can be hereditary, it is important that when buying a puppy you ask carefully if the parents and other close relatives have had any problems with the heart. 

Make sure to keep your dog in good shape. Good basic fitness means that the dog can better cope with stronger stresses on the heart during physical activity.

Agria Vet Guide

If you have an Agria Pet Insurance policy, you have free access to veterinary advice 24/7 through the Agria Vet Guide app. You can download the Agria vet guide here.

Previous article

Ear infections (Otitis externa) in cats

Next article

Teach your puppy to sit and lie down

Related guides and advice


Follow us


For UK customers:
Agria Pet Insurance Ltd is authorised and regulated by the Financial Conduct Authority, Financial Services Register Number 496160. Agria Pet Insurance Ltd is registered and incorporated in England and Wales with registered number 04258783. Registered office: First Floor, Blue Leanie, Walton Street, Aylesbury, Buckinghamshire, HP21 7QW. Agria insurance policies are underwritten by Agria Försäkring.


For Guernsey customers:
Clegg Gifford Channel Islands Limited is licensed by the Guernsey Financial Services Commission. Ref: 2722221. Registered office: Admiral House, Place Du Commerce, St Peter Port, Guernsey GY1 2AT.

© 2024 Agria Pet Insurance Ltd. All Rights Reserved.