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Heart Disease in Dogs: Symptoms, Causes, Treatment

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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 symptoms and causes of these diseases so you can treat 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, symptoms, 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

One of the most common types of heart disease in dogs, chronic valvular disease reduces the amount of blood that can be pumped around the body. The valves that act like doors between the valves of the heart stop working properly, usually by leaking, and reduce the pressure needed to effectively pump blood.

Myocardial Disease

Myocardial disease is the weakening or inflammation of heart muscles, which can cause the improper function of the heart, resulting in the heart pumping inefficiently.

Dilated Cardiomyopathy (DCM)

DCM is a disease of the heart that results in its decreased ability to generate enough pressure to effectively pump blood around the dog’s vascular system.

Genetic abnormalities

Some dogs inherit congenital abnormalities at birth, usually but not always due to breed-specific issues. The most common of these heart diseases include patent ductus arteriosus, pulmonic and aortic stenosis, persistent right aortic arch, and ventricular septal defect.

Symptoms 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 symptoms that can alert you that there’s an issue at hand. Symptoms include:

  • Shortness of breath. Persistent shortness of breath is a common symptom 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 symptoms. This can also be a symptom of other illnesses like pneumonia, but in the case of heart disease, it will be accompanied by other symptoms. You may notice that your dog has more trouble breathing when laying down, leading them to sit or stand for more than usual, accompanied by labored breathing.
  • Cough. If your dog has a persistent cough that doesn’t resolve within a few days, this could be a symptom 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 traveling 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 symptoms.
  • Extreme fatigue. Heart disease can cause dogs to become highly fatigued, to the point where even the smallest amount of exercise tires them out quickly. You may also notice them resting or sleeping far more than usual.

Causes of heart disease in dogs

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While there is usually no single cause of heart disease, nutrition and age have arguably the biggest roles to play. Senior dogs are most likely to develop heart disease, but this may be related to lifelong nutrition and exercise than just old age itself. Common causes of heart disease include:

  • Age
  • Poor nutrition
  • Obesity
  • Lack of exercise
  • Breed genetics
  • Heartworm
  • Environmental factors

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 and regular exercise, will go a long way in the prevention of heart disease.

Diagnosis and treatment of heart disease in dogs

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Image Credit: ESB Professional, Shutterstock

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

  • Stethoscope examination
  • Chest X-rays
  • Blood tests (for heartworm)
  • Electrocardiogram (ECG)
  • Echocardiogram

While heart disease is a serious matter, in most cases, it is treatable, especially in younger dogs. Heartworm can be successfully treated with potent medication, and other issues may simply require an alteration of diet, increased or decreased exercise, and consistent monitoring. For more serious conditions, surgery may be required, but this is not as common as you’d imagine.

While most treatment options will not reverse heart disease, with careful management most dogs can live a relatively normal life. Your vet will help you take the steps to properly manage the disease, but good nutrition will be of the utmost importance.


Final Thoughts

Heart disease in your beloved pooch can be a terrifying prospect, but luckily, in most cases, it can be managed if treated properly. If you catch the signs and symptoms early and get your dog to the vet, they can live a relatively normal life most of the time. Unfortunately, heart disease can be congenital and breed-related, but for most dogs, plenty of regular exercise and a healthy, balanced diet will go a long way in reducing the chances of heart disease later in life.

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Featured Image Credit: Pixabay

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