Breed Health Guide • Reviewed by Dr. Tiffany Delacruz, DVM
Hypertrophic Cardiomyopathy in Ragdolls
Also known as: HCM
Ragdolls have a high inherited risk of Hypertrophic Cardiomyopathy (HCM), the most common heart disease in cats. A specific MyBPC3 mutation (R820W) is well-documented in the breed. The heart muscle thickens, the chambers can't fill properly, and the cat can develop heart failure or a fatal aortic thromboembolism.
Why Ragdolls are predisposed to hypertrophic cardiomyopathy
Ragdolls carry a specific cardiac myosin binding protein C mutation (MyBPC3 R820W) that is distinct from the Maine Coon A31P mutation. The Ragdoll mutation also follows an autosomal dominant inheritance pattern with incomplete penetrance — one copy increases risk, two copies dramatically increase it, and the disease can also occur in cats negative for the known mutation. Genetic testing is widely available and used by responsible breeders.
What you'll see at home
- Often nothing visible early — HCM is silent in pre-clinical stages
- Heart murmur on routine vet exam
- Reduced activity, hiding more, sleeping more
- Increased resting respiratory rate while sleeping (>30/min)
- Open-mouth breathing or panting (urgent)
- Sudden hind-limb paralysis or severe pain (saddle thrombus)
- Collapse or fainting
- Sudden cardiac death (sometimes the first sign)
Red flags — go to an emergency vet
- ⚠ Open-mouth breathing or panting (cats rarely pant — emergency)
- ⚠ Sudden hind-leg paralysis or screaming pain in back end (aortic thromboembolism — saddle thrombus)
- ⚠ Sleeping respiratory rate over 40/min
- ⚠ Collapse, fainting, or severe lethargy
- ⚠ Pale, blue, or grey gums
How vets diagnose hypertrophic cardiomyopathy
Annual cardiac auscultation from kittenhood. Echocardiography by a cardiologist is the diagnostic gold standard. Genetic testing (MyBPC3 R820W) identifies high-risk cats but a negative test doesn't rule out HCM. NT-proBNP blood test screens for cardiac biomarker elevation.
Treatment options
Pre-clinical HCM with no atrial enlargement — monitoring only. Pre-clinical with left atrial enlargement — atenolol and/or clopidogrel commonly added. Clinical heart failure — furosemide, pimobendan, ACE inhibitor, clopidogrel. Saddle thrombus is treated emergently with pain control, anticoagulants, and supportive care; outcomes are often poor.
Common medications for this condition
Don't start, stop, or change any of these medications without a licensed vet's guidance.
Living with a Ragdoll who has hypertrophic cardiomyopathy
- 1 Cardiac auscultation at every vet visit from kittenhood
- 2 Echo screening at age 1, then every 1-2 years
- 3 MyBPC3 R820W genetic test once
- 4 Sleeping respiratory rate at home — weekly check
- 5 Lean body weight, indoor only, minimize stress
- 6 Give cardiac medications exactly as prescribed
- 7 Avoid stressful events for cats with diagnosed HCM
- 8 Know your nearest 24/7 ER for saddle thrombus events
Can RexVet help with this online?
RexVet is well-suited for: atenolol, clopidogrel, furosemide, and pimobendan refills for already-staged Ragdolls; weekly check-ins on respiratory rate and energy; side-effect management; weight management; and triaging new symptoms to decide whether urgent in-person follow-up is needed.
Start a $64.99 video visit →We can't perform echocardiograms, genetic testing, or chest x-rays by video. Acute decompensation (open-mouth breathing, saddle thrombus, collapse) is an ER situation.
Prognosis — what to expect
Pre-clinical Ragdolls with no atrial enlargement often live full normal lifespans. Once atrial enlargement develops, thromboembolism and heart failure risks climb. Clinical heart failure has a median survival of 12-18 months with multi-drug treatment. Saddle thrombus is typically a terminal event for many cats. Early genetic testing and echo screening are the most important levers.
Frequently asked questions
Frequently asked questions
Should I test my Ragdoll for HCM genetics?
Yes — the MyBPC3 R820W test identifies high-risk Ragdolls. A positive test (especially homozygous) warrants more intensive echo monitoring. A negative test reduces but doesn't eliminate risk — Ragdolls without the known mutation can still develop HCM from other causes, so annual auscultation and periodic echo screening are still recommended.
How is Ragdoll HCM different from Maine Coon HCM?
They're caused by different mutations in the same gene — Ragdolls carry MyBPC3 R820W while Maine Coons carry MyBPC3 A31P. Clinically the disease behaves similarly. Both follow autosomal dominant inheritance with incomplete penetrance. Both benefit from echo monitoring, and both have similar treatment regimens once clinical disease develops.
Can a Ragdoll with HCM live a normal life?
Many can — especially when HCM is detected early through echo screening, before any heart failure or thromboembolism. Cats in the pre-clinical phase often need no medication, just monitoring. Cats with atrial enlargement may go onto preventive medications and still live many comfortable years. The big risks are heart failure and saddle thrombus, which can be sudden and devastating.
What does saddle thrombus look like in a cat?
Sudden, severe pain and inability to use the back legs. The cat will often vocalize in pain, drag the hind legs, and have cold or pale-blue back paws (no pulse). It happens without warning, even in cats with no previously known heart disease. It is an absolute emergency — go to an ER vet immediately. Saddle thrombus carries a poor prognosis but immediate veterinary care gives the best chance.
Further reading from the RexVet blog
Sources
- ACVIM Consensus Statement on Feline Cardiomyopathy
- Cornell — Feline HCM
- Veterinary Genetics Lab — Ragdoll HCM Test
Last fact-checked: 2026-06-01. Reviewed by Dr. Tiffany Delacruz, DVM.
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