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Signs of Heart Disease in Dogs

Heart Disease is becoming an increasingly common problem in dogs mostly because more dogs are living longer and surviving other illnesses to enter old age, which is when dogs are more at risk of developing it. This is due to the heart's reduced capability. While there are also heart problems a puppy can be born with heart disease in dogs is more likely in senior dogs. We look here at things that can cause heart disease, the symptoms to be aware of and treatment options to consider.


A Healthy Heart

A dog's heart works and looks the same as a person's, it is a muscle made up of four chambers. Those chambers are separated by valves and make sure the blood is channeled to go the right way. On the right blood is sent to the lungs to be oxygenated and on the left that blood full of oxygen is sent to the rest of the body.

Two Types of Heart Disease in Dogs

There are two main types that affect dogs valvular and expansion of myocardial. In the former older dogs have a problem with heart valves where they no longer close properly anymore which means the blood does not flow in the right direction all the time. This leads to not enough blood being pumped around the body and it affects some breeds more than others such as the King Charles Spaniel.

The latter heart disease is more prone to affect giant and large breed dogs like Irish wolfhounds, Dobermans and Great Danes and is when the cardiac walls expand. This leads to the heart swelling with blood and means it is unable to pump strong enough so not enough blood gets around the dog's body.

Heart Disease Symptoms

The signs of heart disease in dogs can sometimes not be spotted at first as owners will sometimes pass them off as just the dog getting older. Things you will notice include;

Your dog is not as active as he once was and is reluctant to exercise now and less playful.

He needs to rest more often in between limited activity

Loss of appetite when combined with other signs here is an indicator of heart disease.

Loss of weight – while loss of weight tends to be more common in heart disease dogs can actually also gain weight though this is more from bloating or a distended abdomen.

Body tissues may swell from fluid retention known as Edema.

Shortness of breath – can also be labored breathing or rapid breathing.


Coughing – this is such a common symptom of other things too that on its own is not enough to presume heart disease. But if the cough has been prolonged and there are other symptoms you should take him to a vet. Rare but can have seizures

Change in behavior – Dogs with heart disease can withdraw and be reluctant to receive affection from you. They can also appear to be depressed. And they may try to isolate themselves from you and the rest of the family.

Fainting or collapsing.

Weakness – it is true that an aging dog tends to get weaker anyway but again along with other signs here it is more an indicator of heart disease.

Being restless – particularly at night.

Diagnosing Dogs with Heart Disease

If you are concerned about your dog's health even if he is a senior dog so some signs can be put down to that, just take him to a vet for a check up to be sure. The vet can talk about what you have observed and give your dog a thorough physical exam. He or she may also order tests to look for signs of heart disease such as listening with a stethoscope to see if the heart beats abnormally at all, taking an x-ray to see if it is enlarged or changed shape, doing an ultrasound and an ECG.

When you purchase a puppy from a breeder you should have it checked out including a look for congenital heart defects. If they are detected you have the choice of returning to the breeder or having the vet carry out an operation before symptoms worsen.

Treatment and Life Expectancy

In fact a lot of dogs have heart disease and do not display obvious symptoms and lead fairly normal lives without treatment or special care. They might just rest more or play or exercise a bit less intensely. As they reach senior years though the disease does get worse so symptoms will start to show then. Treatment at this point really depends on the otherwise health of the dog, how much longer he has in terms of life expectancy and what you as his owner want to do.

In early stages dogs just need regular check ups with their vet. There is no need for treatment yet just make sure he does get some exercise to keep him healthy and he is eating a healthy diet. When the symptoms show there are drugs and other things that can be done to slow down the disease's progression but they do not completely stop it. Drugs can help make the heart stronger and return the heartbeat to mostly normal and can get rid of the excess fluid the body has collected.


If the heart disease is congenital there is surgery that can be tried to correct the defect. If caught early enough the dog can then make a full recovery with no need for any further treatment.

Life expectancy is something you will have to discuss with your vet. Some dogs live a long and happy life. Some die very quickly. Only your vet can talk to you about how the heart disease has progressed and what kind of life he might have on drugs.