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Home > Dogs > Heart Disease in Dogs: Vet-Reviewed Signs, Causes & Treatment

Heart Disease in Dogs: Vet-Reviewed Signs, Causes & Treatment

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Dr. Marta Vidal-Abarca

Veterinarian, BVSc GPCert (Ophthal) MRCVS

The information is current and up-to-date in accordance with the latest veterinarian research.

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While some dog breeds are more prone to heart disease, it is a condition that can, unfortunately, affect any dog. Several different heart diseases can affect dogs, and it’s a good idea to get to know the signs and causes of these diseases so you can identify and start treating them as early as possible.

Around 10% of all dogs in the United States, almost 8 million, suffer from heart disease. While there are various causes of heart disease, including breed genetics, obesity, and nutrition, old age is the most common time for dogs to develop heart problems. The older your dog is, the higher the risk, and up to 75% of senior dogs have a heart condition of some kind. Unfortunately, a large percentage of these diseases go undetected and can quickly develop into a serious problem.

In this article, we look at the cause, signs, and treatment of heart disease in dogs, as well as the different types of heart issues that they can suffer from.

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Common Types of Heart Disease in Dogs

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Valvular Disease

This is one of the most common types of heart disease in dogs. Chronic valvular disease affects the way the blood is pumped around the body. The valves that act like doors between the valves of the heart stop working properly, usually by leaking, and cause turbulent blood flow that creates a murmur. These can be graded on a scale of 1 to 6. 

Myocardial Disease

Myocardial disease is the weakening and abnormal function of heart muscles, which can decrease the ability of the heart to pump blood efficiently. 

Genetic Abnormalities

Some dogs are born with heart problems; these are called congenital abnormalities and are generally linked to their breed. The most common of these heart diseases include patent ductus arteriosus, pulmonic and aortic stenosis, persistent right aortic arch, and ventricular septal defect.

Signs of Heart Disease in Dogs

There are several other, less common heart problems that dogs can suffer from. However, no matter the specific illness, most of them share common signs that can alert you that there’s an issue at hand. Signs include:

  • Abnormal breathing. Fast or labored breathing are common signs in dogs with heart disease. Since the heart is responsible for pumping oxygenated blood around your dog’s body, breathing issues are usually one of the first signs. This can also be a sign of other illnesses like pneumonia, but in the case of heart disease, it will be accompanied by other signs. You may notice that your dog has more trouble breathing when lying down, leading them to sit or stand for more than usual, accompanied by labored breathing.
  • Cough. If your dog has a persistent cough, this could be a sign of congestive heart failure. Fluid tends to accumulate in the lungs because your dog’s heart is not pumping efficiently, and the enlargement of the heart may also press against airways and cause coughing.
  • Fainting (Syncope). A decrease in heart function results in less oxygenated blood flow through the body. When there is a lack of oxygen getting to the brain during exercise or excessive coughing, it can cause sudden collapse or fainting.
  • Noticeable behavioral changes. Many things can cause sudden marked changes in your dog’s behavior, but heart issues can also cause a few radical shifts. Reduced appetite, long periods of rest and self-isolation, avoidance of interaction, and reluctance to play or exercise are all common signs.
  • Extreme fatigue. Heart disease can cause dogs to become highly fatigued, to the point that they may not be able to cope with small walks. You may also notice them resting or sleeping far more than usual.
  • Bluish mucous membranes. When your dog’s blood is lacking oxygen, their gums and other mucous membranes can develop a blue tinge. 

Causes of Heart Disease in Dogs

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While there is usually no single cause of heart disease, breed, and age have arguably the biggest roles to play. Senior dogs are most likely to develop heart disease, and certain breeds are very prone to specific heart diseases. Common breeds affected by heart diseases include:

  • Cavalier King Charles Spaniel
  • Miniature and Toy Poodle
  • Chihuahua
  • Miniature Schnauzers
  • Maltese
  • Boxer
  • Doberman Pinscher
  • Golden Retrievers

This is why reputable breeders always screen purebred dogs that they intend to breed, to try to pick up any heart defects before they are passed on. This, combined with a healthy diet, regular exercise, and most importantly, regular vet visits, will go a long way in the prevention of heart disease.

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Diagnosis and Treatment of Heart Disease in Dogs

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Image Credit: ESB Professional, Shutterstock

If you’ve noticed any signs in your dog, it’s important to take them for a checkup with the vet immediately. Your vet will perform several diagnostic tests to determine whether there is an issue with the heart, including:

  • Full physical examination
  • Auscultation of the chest (using a stethoscope)
  • Chest X-rays
  • Blood tests (for heartworm or other infectious diseases)
  • Electrocardiogram (ECG)
  • Echocardiography (heart ultrasound)

While heart disease is a serious matter, in most cases, your dog can live a fulfilled and long life if the issue is caught on time and you follow your vet’s or cardiologist’s instructions. The treatment usually consists of a combination of different medications, exercise modification, treating any underlying issue, such as heartworm, or a change in diet. For some congenital conditions, surgery may be required, but this is not as common as you’d imagine.

While the majority of the time heart disease can’t be reversed, with careful management, most dogs can live a relatively normal life. Your vet will help you take the steps to properly manage the disease, and it is essential that you work alongside them.


Final Thoughts

Heart disease in your beloved pooch can be a terrifying prospect, but luckily, in most cases, it can be managed so that your dog can have an excellent quality of life. Be especially vigilant if your dog belongs to a breed predisposed to heart disease. If you catch the signs early and start treatment promptly, they are more likely to live a relatively normal life for many years. Unfortunately, heart disease can be breed-related. That is why responsible breeding is essential to minimize these conditions in future generations.

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Featured Image Credit: Pixabay

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