Canine Cardiomyopathy Diagnosis

Canine cardiomyopathy, also known as dilated cardiomyopathy or DCM, occurs when the chambers of the heart become enlarged and can no longer contract as powerfully as they once did. Cardiomyopathy is common, and is one of the primary causes of canine congestive heart failure. Here's what you should know about cardiomyopathy in dogs.

Risk Factors for Cardiomyopathy

Canine cardiomyopathy appears to affect certain breeds more than others. Breeds prone to this disorder include Doberman Pinschers, Old English Sheepdogs, Great Danes, Dalmatians and Saint Bernards. In general, large breed dogs are more vulnerable to this condition than smaller breeds, though English and American cocker spaniels are also particularly susceptible to it.

Dogs typically develop cardiomyopathy between four and ten years of age, though some breeds, such as the Portuguese water dog, can develop cardiomyopathy at a younger age.

Consequences of Canine Cardiomyopathy

Canine cardiomyopathy can cause heart murmurs, arrhythmias and leakage around the valves of the heart. Your dog's heart loses its ability to contract powerfully enough to pump blood efficiently, and your dog could suffer from symptoms of oxygen deprivation because the tissues of his body aren't getting the blood flow that they need.

One of the most serious risks of cardiomyopathy in dogs is congestive heart failure. Cardiomyopathy causes leaking around the valves of the heart, and could allow blood to flow backwards through the chambers of the heart. Eventually, blood and other fluids can build up in the chest cavity around the heart, exerting pressure on the muscle and inhibiting its ability to function properly. Without treatment, congestive heart failure can cause death; cardiomyopathy in dogs is a serious and life threatening condition.

Symptoms of Canine Cardiomyopathy

If your dog suffers damage to the heart muscle due to cardiomyopathy, he could experience some or all of the following symptoms:

  • Shortness of breath
  • Unwillingness to exercise
  • Coughing
  • Loss of appetite
  • Swelling of the abdomen
  • Episodes of collapse
  • Decreased appetite
  • Lethargy

If your dog develops these symptoms, seek emergency veterinary care. Canine cardiomyopathy can cause heart failure and death.

Diagnosing Canine Cardiomyopathy

Your vet will need a complete medical history and a thorough physical exam in order to diagnose canine cardiomyopathy. Your vet may use EKGs, chest X-rays and cardiac ultrasounds to determine the extent of the damage to the heart muscle and its function. Blood tests and biochemical profiles can help your vet determine if your dog is suffering from an underlying or secondary illness, or if complications of cardiomyopathy have occurred. Blood pressure measurements can tell your vet how far your dog's cardiomyopathy has progressed.

Treating Cardiomyopathy in Dogs

Your vet will recommend making dietary changes to help slow the progression of your dog's cardiomyopathy. Your dog will need a reduced sodium diet. He may benefit from using nutritional supplements, such as taurine or L-carnitine.

Your vet will probably prescribe some kind of medication to help stop damage to your dog's heart muscle. In the case of arrhythmia, medication can stabilize the electrical impulses that cause your dog's heart to beat regularly. When congestive heart failure has already occurred, diuretics are prescribed to help flush excess fluids from your dog's abdominal cavity.