Cats can be victims of several types of heart disease. Heart disease in cats is frequently diagnosed and it can be a frightening situation for a cat owner.  Understanding heart disease in cats will help you better cope with your pet’s illness as well as recognize warning signs to avert an emergency situation.

Your Cat's Heart

The heart is a muscle that pumps blood around the body. It is made up of four chambers. The two top chambers are called the atria. The two chambers on the bottom are the ventricles, which pump blood out of the heart. The septum is a thick wall of muscle that runs down the middle of the heart, separating the right and left sides. Deoxygenated blood from the body flows into the right atrium, through the tricuspid valve into the right ventricle. It is then pumped out through the pulmonic valve and via the pulmonary artery to the lungs. Oxygenated blood then flows from the lungs, via the pulmonary vein, into the left atrium. It then continues through the mitral valve into the left ventricle where it is pumped out through the aortic valve and via the aorta to supply blood to the body.


Cardiomyopathy is the most commonly diagnosed feline heart disease. Cardiomyopathy means primary heart muscle disease, it is not caused by anything else going on within the body. This disease starts in the heart.


There are four forms of cardiomyopathy that are seen in cats:

  • Hypertrophic Cardiomyopathy (HCM), for more >>

  • Restrictive Cardiomyopathy (RCM), for more >>

  • Dilated Cardiomyopathy (DCM), for more >>

  • Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC).


It is thought that cardiomyopathy in cats is a familial, genetically inherited disease caused by a genetic mutation. Note: This is different from a congenital disease. A congenital disease is one with which the cat is born, it is present at birth.

In cardiomyopathies, the 'bad' gene is present from birth, but the disease that we see develops over time and usually does not manifest until cats are adult.


Initial analysis of family trees indicate that cardiomyopathy in Birmans is likely a genetically inherited disease. The majority of cardiomyopathy in Birmans has been HCM, however RCM is also seen. Birman cats have been reported to develop ARVC more frequently than other breeds.