Dog Enlarged Heart Condition


"A dog with an enlarged heart can be difficult to diagnose until symptoms such as breathing, cough, collapse and an enlarged abdomen start to appear. While there is no cure there are several drugs that can help prolong the life of your dog."


A dog with an enlarged heart condition is the most common cause of heart failure in large dogs. With this condition a dog's heart enlarges causing it to have trouble pumping blood and with the way it moves calcium ions. With a decline in the ability to move calcium, the heart becomes thinner and flabby.

Over a few months, the thinning causes the heart to become enlarged (dilated) and the timing of the heart changes for the worse, causing the dog to start showing symptoms. When the condition worsens, it results in heart failure and sadly after 1 to 2 years, the death of your dog.

The cause of the disease is not known but is associated with parvovirus, taurine deficiencies and adriamycin. The disease tends to affect male, middle age, large breeds of dogs and is most often seen in Doberman Pinschers, Saint Bernards, Cocker Spaniels, Great Danes, German Shepherds and Labrador Retrievers. It is not common in small dogs. 

Symptoms of Canine Enlarged Heart

Signs of a dog with an enlarged heart include heart failure, difficulty breathing, cough, collapse and an enlarged abdomen due to fluid. If your dog is showing these symptoms, the disease has progressed to a later stage.

Diagnosis of an Enlarged Heart

All of the common methods used to diagnose canine heart disease are used to diagnose an enlarged heart. Surgery is not needed to diagnose this disease.
Methods of diagnosis include:

  • X-Rays - To check for enlargement
  • Electrocardiography (electrical reading of heart) - Records arrhythmia (pattern of heart beats) and allows the Veterinarian to see the size of the heart chambers
  • Echocardiography (ultrasound) - Provides a definitive diagnosis

Treatment of an Enlarged Canine Heart

There is no cure for this disease. Several heart treatment drugs are often prescribed for dogs and used in combination to treat an enlarged heart.

Drugs include Digoxin (helps with heart contractions), ACE Inhibitors (reduces blood pressure) and diuretics (removes water, works on kidneys).

Canine Enlarged Heart Diet and Supplements

All dogs with heart issues are put on a low-salt diet to reduce liquid retention. Recent studies are showing that if a dog's diet is low in taurine, they see future heart problems. Dietary supplements may help your dog such as:

  • Taurine - Amino acid produced naturally by dogs. This substance helps to regulate heartbeat, helps calcium absorption during times of reduced oxygen and protects the heart from calcium overload. In order to produce taurine (from vitaimin B-6, dogs also need the substances methionine and cystine). Other good supplements are vitamins C and B-1. Note that taurine has been found to be particularly effective in Cocker Spaniels. Taurine has no known side effects, but safe dosage should be based on the recommendation of a Veterinarian.
  • Carnitine and Coenzyme Q - Also often recommended by Veterinarians as they help with an enlarged heart condition by bringing fatty acids into muscle cells which are then converted into the needed energy. These supplements are considered safe. Try not to use D-carnitine or DL-carnitine which may cause problems with muscle function and possibly angina.

A good source for natural heart supplements is PetAlive Heart & Circulation - for the Natural Treatment of Heart Disease.

Life Expectancy in Dogs With Congestive Heart Failure

While every dog is different, how long your dog will live depends on whether he or she responds to treatment. You should see some type of positive response the day drugs are administered or within several days.

The long term prospects for any dog with this disease are not good. Doberman breeds often pass away in 1 to 6 months. Dogs that are most responsive to treatment are Cocker Spaniels (when they are taurine deficient and add carnitine), Boxers, (carnitine) and others that respond to taurine therapy.


"Home Care of the Heart Failure Patient"
Nelson, O.R.
Washington State University

"Canine Heart Disease"
Dukes, Joanne, MRCVS Department of Veterinary Medicine University
Glasgow Veterinary School, Scotland, UK

Hearty Dog,

Heart Disease in Dogs and Cats
Hines, Ron DVM, PHD

Heart Conditions: Dilated Cardiomyophaty (DCM) "Treatment for Rapid Heart Beat"
Yankee Golden Retriever Rescue

"His Heart is In Your Hands"
Canine Cardiology, New Hope Animal Hospital

"Canine Dilated Cardiomyopathy and Heart Failure"
Pawprints & Purrs, Inc.

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Dr. Clarke E. Atkins
Texas A&M University College of Veterinary Medicine and Biomedical Sciences