Heart Disease In Dogs - What You Need To Know

Heart Disease In Dogs - What You Need To Know

Heart disease is a pretty big deal in humans, so you can probably guess that it is the same for dogs. A part of your job as a dog parent is to take the necessary steps to educate yourself about this condition and your role in preventing and treating it.

Dog hearts

Understanding heart disease in dogs begins with understanding dog hearts. Like us, a dog’s heart has four chambers, which we can consider as rooms. Between these rooms are valves which we can think of like doors. There are also veins and arteries that we can think of like hallways going in and out of rooms that carry blood into the heart and from the heart to the rest of the body, i.e the lungs (pulmonary circulation), and the rest of the body (systemic circulation).

When your dog has heart disease, it affects the way the heart pumps blood to the body. This can very quickly become life-threatening as blood can begin to back up in the lungs, and organs become starved of oxygen.

Types of Heart Disease In Dogs

While heart disease boils down to the inability of the heart to pump blood properly, it depends on which parts of the heart aren’t functioning properly. The main types of heart disease seen in dogs include:

  • Degenerative mitral valve disease- This is the most common form of heart disease in dogs where degenerative changes in the valve between the top and bottom chambers on the left side of the heart cause it to leak. This leads to bump being pumped back into the top chamber when the heart contracts rather than forward into the systemic circulation.
  • Dilated cardiomyopathy- This occurs when the heart muscle becomes weaker and thinner over time which affects its ability to pump blood.
  • Heartworm disease- This is the result of a parasitic infection where large worms in the chest contracted from mosquito bites damage the pulmonary artery, blocking blood flow to the lungs. They may also wiggle their way through the chambers and valves, causing irreversible damage to the heart.
  • Heart murmur- This is where the heart makes abnormal sounds due to disruption in blood flow caused by an issue with the valves of the heart. It is a result of them lagging behind the other instead of opening and closing in a normal rhythm.

Signs of Heart Disease

Some signs your dog may have heart disease include:

  • Excessive coughing
  • Low energy
  • Loss of appetite
  • Higher respiratory rate
  • Pale or blue-tinted gums


In many cases, heart disease is not preventable, however, it is treatable. This can take the form of medication and more than regular visits to the vet. As heart disease gets worse over time, treatment may have to intensify and visits may have to increase.


Avoid grain-free and exotic protein food options to help prevent heart disease in dogs. You should also ensure your dog gets enough exercise and maintains a healthy weight.

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