Hypertrophic cardiomyopathy: Hypertrophic cardiomyopathy (HCM) is the most common style of cardiovascular disease in cats. During this situation, the wall from the still left side of the guts, which pumps blood out to the rest of the human body, thickens with time.Very pleased mom of four Sphynx kitties! I adopted all of my lovable feline buddies