HCM - Hypertrophic Cardiomyopathy - What is it and What does it mean?
What is HCM?
Hypertrophic Cardiomyopathy – the most common of acquired heart diseases in cats. It is a heart muscle disease where the left ventricle becomes thickened over time. It can happen at any age. It causes the heart to stop functioning as it should which can in turn cause blood clots, and it otherwise affects the structure and functioning of the heart. There is no cure, but the condition can be medicated. Some cats with HCM can live long and happy lives as long as they are medicated. It is a disease also know in humans. Some cats will only have a mild case, whilst others may be severe which may cause death.
Is sphynx the only breed it happens to?
There are many breeds known to be affected by HCM, including domestic cats, Maine Coons, Ragdolls, Norwegian Forest Cat, Siberian, just to name a few
Why should that mean anything to me?
With sphynx, HCM is thought to be genetic, although it can skip generations and turn up at any time. If an ancestor of a sphynx has been diagnosed for HCM, there is a disposition for the risk, but it does not mean the cat will develop HCM.
How can you test for it?
We recommend that all sphynx are tested. Due to the nature of the disease, you cannot test until they are 12 months old. We recommend this for all breeding cats and then annually. For all pet sphynx we recommend testing at least every 18 months from 12 months of age. Testing can vary in cost and is expensive, but well worthwhile.
- There is no value in dna testing sphynx for HCM as there is no dna test for sphynx (there is a dna test for ragdolls and for one of the two known genes in Maine Coon)
- Pro-BNP Blood test may indicate an issue with the heart, but it is not HCM specific. There is also a large error factor when using this test to diagnose HCM in sphynx
- Echocardiogram – this is the gold standard for testing sphynx for HCM, and should be done by a feline cardiologist, not a general vet. There are currently five certified feline cardiologist in Australia. When purchasing a sphynx please ask to see original documentation of HCM results and if not possible, then ask for authority to contact the specialist to verify results.
Dr Fiona Campbell BVSc(Hons), MANZCVS, PhD, Dip ACVIM (Carrara, QLD) www.vss.net.au
Dr Brad Gavaghan BVSc MACVSc FACVSc (Brisbane, QLD) www.vss.net.au
Dr Richard Woolley BVETMed, Dop ECVIM-CA, MRCVS (Victoria) www.cprvictoria.com.au
Dr Rita Singh BSC,BVNS(Hons) Dip Vet Clin Stud, FACVSc, Dip AVCIM (Sydney) www.sashvets.com
Dr Niel Beijerink DVM, PhD, Dip ECVIM-CA (Sydney) www.sydney.edu.au/vetscience
What does it mean for my nakid?
When you are considering buying a sphynx, please verify the breeders stance on testing and ask for copies of current documentation or guarantees against HCM. Also ask for a copy of the pedigree and use the following websites to investigate the known incidence of HCM in those pedigrees before purchasing.