10 Symptoms of Canine Heart Murmur

A canine heart murmur is caused when the blood flows abnormally in a canine heart. The abnormal change in the dog heart can cause the right side of the heart to not communicate well with the left side, sometimes affecting a dog's health.

Symptoms of a Heart Murmur in Dogs

  • The dog's heartbeat seems irregular
  • A hacking cough that does not seem to go away.
  • Breathing that seems labored (excessive panting) even while the dog is resting
  • The canine tires easily
  • Lack of energy
  • Collapsing or fainting
  • The gums or tongue have a bluish color
  • A racing pulse
  • Severe water retention
  • Lack of appetite

All of these symptoms may indicate health risks that are serious, but not necessarily a murmur. Only a veterinary doctor can diagnose a heart murmur in dogs.

Causes of Heart Murmurs in Dogs

Dogs can develop heart murmurs for a number of reasons. Some dogs may develop heart disease as they age, causing them to have an irregular heartbeat. Blood leakage from the heart valves to the atrium or high blood pressure could also be a cause. Some puppies are born with a birth defect that causes murmurs or they may be more genetically prone to this condition. Dogs that have anemia or a disease that affects the heart or blood vessels could make a canine more prone to developing a heart murmur.

Mitral valve stenosis, a condition in which the heart's valves leak, can result in a heart murmur in dogs. A condition where holes are present in the chamber that pumps blood, ventricular septal, can cause the blood to flood too rapidly in puppies, resulting in an irregular heartbeat. Pulmonary or aortic stenosis, the narrowing of the pulmonary or aortic artery, can cause an irregular blood flow, resulting in murmurs in dogs.

Diagnosing Heart Murmurs

When there is suspicion of a heart murmur in a canine, doctors will perform several different tests to confirm their diagnosis.

  • Listening to the heart with a stethoscope
  • Chest x-rays
  • Heart ultrasound: to see all almost all of the functions of a dog's heart in real time and see if the heart has any irregularities
  • Blood and urine tests: to check for any abnormalities in liver and kidney function
  • Electrocardiogram: an assessment of the dog's heart activity over a period of time

Treating Heart Murmurs in Dogs

Heart murmurs in dogs can be nothing to worry about or a condition that can progressively get worse. If a puppy is found to have a murmur, it may not be treated until health problems are present. Heart murmurs cannot be cured, but they can be treated surgically, with medication, or dietary changes.

If you suspect your dog may have a problem with his or her heart, see your veterinarian as soon as possible. Share your concerns and questions with your vet and tell them about any lifestyle and activity changes.