Enlarged Heart in Dogs (Dilated Cardiomyopathy)

Source: PetWave, Updated on July 16, 2015
Dilated Cardiomyopathy

Definition of Dilated Cardiomyopathy

Dilated cardiomyopathy, or DCM, is a disease characterized by an enlarged heart. Dogs with DCM have abnormal heart muscle fibers which prevent the heart from contracting properly. Blood backs up, causing the heart chambers to stretch and thinning their walls. This further impairs the heart’s ability to pump and reduces the amount of circulating blood. All tissues are adversely affected by decreased delivery of oxygenated blood; the lungs and kidneys are especially vulnerable. Congestive heart failure and/or heart rhythm abnormalities often accompany DCM, especially in large dogs. What causes DCM isn’t known. A number of things have been suggested, including malnutrition, immune system problems, infection and genetics. Most dogs with DCM seem unaffected by their condition early-on. As DCM progresses, affected animals usually cough and develop frightening, painful breathing problems. In most cases, this disease ultimately is fatal.

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