noun. A disease or disorder of the heart muscle, especially of unknown or obscure cause.

noun. The deterioration of the myocardium.

noun. a disorder (usually of unknown origin) of the heart muscle (myocardium)

"Many benefit from consultation with a specialist in cardiomyopathy and may be referred to other specialists in metabolism, genetics, and or neurology, if an inherited or systemic disorder related to cardiomyopathy is suspected."