Hypertrophic Cardiomyopathy in Cats
What is Hypertrophic Cardiomyopathy (HCM)?
- HCM is the most common form of heart disease in cats and is the result of a genetic mutation(s).
- HCM causes progressive thickening (hypertrophy) of the heart muscle (left ventricle) and dilation of the left atrium. (See Figure).
- Over time the thickening can create a stiff heart possibly resulting in congestive heart failure (fluid in or around the lungs).
- Signs of congestive heart failure in cats are increased breathing rate or effort, lethargy, decreased appetite, and/or reclusive behavior.
- Younger cats often develop a more aggressive form of the disease than older patients.
- Older cats can develop a thickened heart muscle from other conditions such as overactive thyroid, kidney disease, or high blood pressure.
How is it diagnosed?
- Your primary care veterinarian will refer you to a board certified veterinary cardiologist because they heard a heart murmur, arrhythmia or found an elevation in a blood test called NT-proBNP as part of your cat’s annual or every six month wellness evaluation.
- An echocardiogram (ultrasound or sonogram of the heart) by a board certified veterinary cardiologist is the gold standard for definitive diagnosis.
How do you treat HCM?
- Most patients benefit from medical therapy – readily available heart medications of the same variety used in human patients.
- Given the variable and unpredictable nature of HCM, medication needs often change over time; therefore, vigilant monitoring and consistent follow-up is required to prevent congestive heart failure.
- With appropriate medication and early intervention, we can often achieve stabilization of the disease process and sometimes reversal of some of the cardiac changes.
How will my primary care veterinarian be involved?
- We collaborate with you and your primary care veterinarian to prevent, delay, and eliminate signs of congestive heart failure while providing your cat optimal quality and length of life.