Canine Restrictive Cardiomyopathy The enlarging of the heartโ€™s chambers

Canine Restrictive Cardiomyopathy

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Canine Restrictive Cardiomyopathy is a disease that affects dogs. This condition can make breathing difficult for your dog and lead to other health problems.

Canine restrictive cardiomyopathy (CRM) is a rare condition affecting any dog breed, though it often occurs in middle-aged to older, purebred dogs. CRM causes the heart to become stiff and rigid, causing symptoms such as shortness of breath and fainting.

It's essential for you to seek treatment for your dog early on, as CRM has no cure and can be fatal. The causes of canine restrictive cardiomyopathy are unknown but seem to affect certain breeds more than others.

A common theory suggests that the disease results from abnormal development during pregnancy, which leads to an incompletely developed heart muscle that does not expand fully once it develops in utero. Generally, 0.2 to 3.5% of canines are born with some genetic defect. 

Canine Restrictive Cardiomyopathy Causes

Canine restrictive cardiomyopathy is an inherited form of heart disease that affects dogs. It means that it's passed down through a dog's DNA genes and can be passed on by mating with another dog with the disease.

The heart is a muscle that pumps blood throughout the body, so if your dog has a weak or damaged heart muscle. It may need more energy to do all of its usual activities or tire quickly after doing something seemingly simple like walking across the yard. They may also have trouble breathing normally and feel like they're struggling for air. 

Canine Restrictive Cardiomyopathy Diagnosis

Canine restrictive cardiomyopathy can be challenging to diagnose, but it's essential to get a correct diagnosis as soon as possible. Your veterinarian will perform a physical exam and conduct blood tests to determine if your dog has the disease.

A chest X-ray may also reveal signs of heart failure: dilated cardiomyopathy in which the left ventricle is enlarged and underdeveloped, or fluid accumulation around the lungs indicates pulmonary edema.

Cases that are severe enough for diagnosis require an echocardiogram; an ultrasound of your dog's heart muscle allows veterinarians to see how well each chamber functions from the inside out. 

Canine Restrictive Cardiomyopathy Treatment

Your dog can live a longer, more comfortable life by receiving medications, oxygen therapy, or surgery. Drugs are used to treat the symptoms of restrictive cardiomyopathy. The treatment of canine restrictive cardiomyopathy depends on the severity of the disease. In mild cases, pet medication can be used to treat this disease.

Depending on the severity of your dog's condition and his response to pet medication, he may need to be hospitalized for treatment. In some cases, he might also need long-term oxygen therapy or surgery to relieve respiratory distress. 

Canine Restrictive Cardiomyopathy Symptoms

Restrictive cardiomyopathy can be detrimental to your dog. Learn more about the symptoms of this disease:

  • Difficulty breathing, i.e., dyspnea, coughing, especially when lying down, for which the vet may prescribe cough medicine for dogs to reduce the symptom.

  • Lack of energy, i.e., lethargy, which can be managed to an extent using a diet like Diamond Naturals, Eukanuba, etc., or extra supplements like salmon oil, which are easy to find in pet supplies stores.

  • Fainting (syncope),

  • Fluid build-up in his lungs (pulmonary edema).


Dogs with CRM have decreased blood flow to the heart muscle, which causes it to weaken. As a result, the chambers of their hearts become enlarged and thicker than usual. It means there's less room for blood to pump through them, so it doesn’t get enough oxygenated blood. 

The weakened muscles can't beat as vigorously or as often as they should be able to do either, resulting in an inefficient heart rate and reduced output from each heartbeat. Remember that if your dog has any symptoms of heart disease, it's essential to see a vet immediately so they can be diagnosed and treated correctly.

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