Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) familial hypertrophic cardiomyopathy ?
    ### Response:
    Familial hypertrophic cardiomyopathy is a heart condition characterized by thickening (hypertrophy) of the heart (cardiac) muscle. Thickening usually occurs in the interventricular septum, which is the muscular wall that separates the lower left chamber of the heart (the left ventricle) from the lower right chamber (the right ventricle).
    