Hypertrophic cardiomyopathy is the most common heart disease in cats, often developing silently before causing sudden heart failure or other serious complications.
Cats with HCM experience progressive cardiac compromise that causes respiratory difficulty, decreased exercise tolerance, and risk of sudden death. Congestive heart failure causes respiratory distress as fluid accumulates in or around the lungs, a frightening and uncomfortable experience. Aortic thromboembolism, a catastrophic complication, causes acute paralysis of the hindlimbs with severe pain. Careful monitoring and medication can extend comfortable life, but the condition requires attentive management and difficult end-of-life decisions.