Cat Hypertrophic Cardiomyopathy Monitoring

Hypertrophic cardiomyopathy is the most common heart disease in cats, often silent until life-threatening complications develop, making regular screening vital for welfare.

Key Facts

HCM involves thickening of the left ventricular wall, reducing cardiac output and increasing pressure
Many cats remain asymptomatic for years before developing congestive heart failure or arterial thromboembolism
Maine Coons and Ragdolls have a particularly high genetic predisposition to HCM with known mutations
Auscultation detects murmurs or gallop rhythms but echocardiography is required for diagnosis and staging
Congestive heart failure presents as acute respiratory distress requiring emergency treatment
Arterial thromboembolism causes sudden hindlimb paralysis and severe pain and often warrants euthanasia

Welfare Considerations

HCM causes welfare harm through two main crisis events: acute congestive heart failure with severe respiratory distress, and arterial thromboembolism causing extreme pain and sudden paralysis. Both are preventable to some degree through early detection and prophylactic treatment in high-risk cats. Regular echocardiographic monitoring of at-risk breeds allows early identification of significant disease before crisis occurs. Aspirin or clopidogrel treatment in cats with enlarged left atria reduces thromboembolism risk. The welfare case for regular screening in predisposed breeds is compelling given the severity of consequences from late presentation.

What You Can Do

Have at-risk breeds including Maine Coons and Ragdolls screened by echocardiography annually
Request echocardiography if your vet detects a murmur or gallop rhythm in your cat
Discuss prophylactic clopidogrel treatment with your vet if your cat has moderate to severe HCM
Learn to recognise respiratory distress in your cat and seek emergency care immediately if it occurs
Support genetic testing programmes in cat breeding to reduce HCM prevalence in predisposed breeds