Signs of Heart Disease in Dogs

Symptoms of congestive heart failure in dogs include a cough.


The most common type of heart failure in dogs is congestive heart failure, which is left-sided heart failure. The left side of the heart receives the freshly oxygenated blood and sends it back out to the body. If the left ventricle can’t pump enough blood, fluid can begin to back up in the lungs and other parts of the dog’s body. This may produce the signs of heart disease in dogs that you can recognize.

How do you know if your dog has heart disease? If you see these general signs – weakness, lethargy, lack of appetite, difficulty breathing, everyday walks take longer over the same route – something is wrong with your dog.

Symptoms of Congestive Heart Failure (CHF) in Dogs

A heart disease cough is a real sign of left ventricle heart disease, but a cough alone is not enough to indicate heart failure in your dog. A heart disease cough can be loud and honking like a cough due to tracheobronchitis (kennel cough) because, as the heart fails, it begins to enlarge due to blood backing up. When that happens, the heart muscle must work harder and sometimes starts pushing up on the trachea, inducing a tracheal cough. But that cough might be just kennel cough, too. A thorough physical examination and chest x-rays can usually solve this conundrum.

Signs of left-sided heart failure in dogs include:

  • Changes in the dog’s breathing
  • Heart disease cough
  • Exercise intolerance
  • Restlessness
  • Discomfort lying down
  • Lethargy
  • Weakness
  • Lack of appetite
  • Collapse

Noticeable Signs of Heart Failure

If a dog is battling heart failure, you may notice that his respiratory rate elevates as his body tries to get more oxygen. Normal respiratory rate is less than 30 breaths per minute (bpm). Monitoring your dog’s sleeping respiratory rate is a good way to catch CHF in its earliest stage. If it rises above 35 bpm and stays elevated, have your dog examined by a veterinarian.

This is especially important for dogs with heart murmurs, as murmurs significantly increase the risk of developing CHF in dogs. Breathing will eventually become labored, which looks like your dog is pulling hard to get air in and to get air out. It typically involves noticeable pushing from the abdomen.

You also may notice a change in how long it takes to complete your walks. A route that used to take 30 minutes now takes 45 minutes. This may be an early indicator of exercise intolerance. Sometimes it’s more obvious. Your dog just quits on your walk; sits or lies down, usually panting/breathing hard, and refuses or is unable to continue.

Right-Sided Heart Failure in Dogs

The right side of the heart receives blood coming back from the rest of the body and sends it to the lungs. When the right side begins to fail, fluid backs up in the body. You may notice:

  • A big, swollen, fluid-filled belly (abdominal effusion)
  • Increased respiratory effort because of the swollen belly
  • Fluid accumulating around (not in) the lungs (pleural effusion)
  • Swelling of the lower limbs that shows your fingerprint when you press on it (pitting edema)
  • Restlessness
  • Discomfort lying down
  • Weakness
  • Lethargy
  • Lack of appetite

Catch Heart Failure in Dogs Early

If you notice any subtle changes along these lines, the sooner you have your dog examined and begin a heart disease medical treatment plan, the longer and more comfortably your dog will live. Annual wellness exams are a great way to catch signs of heart disease in dogs as early as possible.