HCM in Ragdoll Cats

HCM in Ragdoll Cats

A reader wrote in telling me her kitty suddenly passed of HCM.  She has asked that I re-run this guest post by Lorie Huston – may she RIP.


Originally published Jul 26, 2012

The other day a Floppycats reader emailed me concerned that her kitten might have HCM, I did not have a good idea of what all it entailed.  So I reached out to Lorie Huston, DVM to see if she could provide insight for us.  Thank you to Lorie Huston, DVM for writing this  – please feel free to ask questions!

Guest Post by Lorie Huston, DVM

Hypertrophic cardiomyopathy, or HCM, is the most common form of heart disease seen in cats. In Ragdolls, most cases of HCM are inherited from the parents and caused by a gene mutation. Fortunately, we have DNA tests that can detect if a specific cat is carrying the mutation. Unfortunately, we don’t have a cure for HCM at this time, although medications are available that may help some cats.

Affected Ragdoll cats may inherit a mutated gene from just one parent (which is referred to a heterozygous) or a mutated gene from both parents (referred to as homozygous.) In Ragdolls, cats that are heterozygous tend to have a milder form of the disease than those that are homozygous although the disease can still be very serious even in heterozygous cats. (This varies in other cat breeds as the specific mutation and the means of inheritance varies from breed to breed.)

Hypertrophic cardiomyopathy affects the heart muscle, causing the muscle to become thickened, resulting in an inability to pump blood normally through the heart. In most cases, the left side of the heart is the most severely affected, leading to left-sided heart failure.

Symptoms associated with HCM include:

  • Difficult breathing.
  • Increased respiratory rate.
  • Increased respiratory effort.
  • Increased heart rate.
  • Weakness.
  • Lack of appetite.
  • Lethargy.
  • An irregular heart rate (arrhythmia) which may cause fainting episodes.
  • Cyanosis due to lack of oxygen.
  • Hind leg paralysis and/or pain due to a blood clot lodged in the aorta (aortic thromboembolism). In this situation, a blood clot breaks off from within the heart and travels through the aorta, becoming lodged at the end of the aorta blocking the flow of blood to the hind legs.

DNA testing can reveal whether your cat carries the gene mutation most commonly responsible for HCM. However, the only way to accurately evaluate how your cat’s heart is functioning is via an echocardiogram. Though the inherited heart disease caused by the gene mutation is the most common cause of HCM in Ragdolls, there are other causes as well. For instance, hyperthyroidism has been implicated in causing toxic changes within the heart that may cause cardiomyopathy. (Some cardiologists argue that these cases are not accurately referred to as hypertrophic cardiomyopathy but the symptoms are still similar.)

An echocardiogram is an ultrasonographic evaluation of your cat’s heart and allows direct visualization of the heart muscle and individual chambers of your cat’s heart. A cardiologist can measure the muscle thickness and determine whether your cat’s heart is pumping blood through its various chambers effectively and efficiently.

Most cats with cardiomyopathy will need to have an echocardiogram performed on a periodic basis to monitor progress of the disease.

There are a number of drugs that are used to HCM.

  • Furosemide (Lasix) is a diuretic and is used to treat congestive heart failure by removing excess fluid accumulating in the lungs and other body tissues because of the heart failure. Another diuretic less commonly used is spironolactone.
  • Enalapril and benazepril are ACE inhibitors (angiotensin-converting enzyme inhibitors). These drugs help HCM cats by causing vasodilation, or opening of the blood vessels, making it easier for the heart to pump blood.
  • Pimobendan (Vetmedin) is a drug that causes both vasodilation and an inotropic effect which causes the heart muscle to contract with a greater force.
  • Anticoagulants are often used in an attempt to prevent or control blood clots. Aspirin and clopidogrel (Plavix) are the two most commonly used anticoagulants.
  • Cats with HCM may have elevated blood pressure also. Medications which lower blood pressure may be necessary and include amlodipine and atenolol.
  • Supplements such as taurine, L-carnitine and coQ10 are sometimes used as well but their effectiveness is questionable.

Thanks again to Lorie for helping us understand HCM in Ragdoll cats!  Please join Lorie on her website – Pet Health Care Gazette

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Hi, I’m Jenny Dean, creator of Floppycats! Ever since my Aunt got the first Ragdoll cat in our family, I have loved the breed. Inspired by my childhood Ragdoll cat, Rags, I created Floppycats to connect, share and inspire other Ragdoll cat lovers around the world,

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  1. Teresa Reid says:

    Thank you and feel the same as Patti – hope we never need this as both babies were tested and it was negative. Miss Mari has been really healthy for her 9 years here, so hope that is a good indicator that she is OK. So sorry for all the kitties (and their human parents) who lost their lives to this horrible disease.

  2. Patti Johnson says:

    Thank you so much for this very important information on HCM, Jenny & Dr. Huston! I will save this and hope I never have to refer to this info!

    Big hugs!

    Patti & Miss Pink Sugarbelle 🙂 <3

  3. Cindi Marescalchi Pike says:

    Hi. I have what I believe to be a male rag doll. He is 4 years old. Good health. Very skittish but lovely too. His sister, Lily passed away yesterday unexpectedly. She was much thinner in comparison.

    My ex husband owned her and is devastated. She didn’t like going to vets, of course, so the vet prescribed a sedative. Her dad gave it to her put her in crate, and soon after she was dead in the crate.

    Very traumatic for him as he loved her very much and wanted her to be seen by vet for a wellness check.

    When we got to vet, she stated that Lilys intestines were thickened and she probably had a malignancy and the stress on her body from that caused her to die. She was thin but ate and pooped fine from what I’m told.

    My ex thinks he killed her by giving her that pill. He is crushed. But the vet thinks she had cancer and was dying.

    Now looking up info, I’m curious if she had HCM. We won’t know as she was or will be cremated. However I have her brother and just need some guidance. I’m afraid of getting him so stressed to go to vet that he’s going to have a heart attack on me. And I’m afraid of sedating him to get a genetic test. Can my local vet do the test for HCM?

    Please help. This has been an awful 24 hours. Thank you.

    1. Catherine Stewart-Mott says:

      Wow, sounds so similar to my cat’s experience. He went in for a first time constipation issue, but it was apparently quite bad so they hospitalized him, did a before/after xray, as well as subcutaneous fluids (he wasn’t eating/drinking well) and a rash of enemas. It wasn’t until he came home that I truly appreciated just how stressful it must have been for my gentle and timid cat. He did not really improve, and I ended up having blood work and then another (chest) xray done as he seemed to be swallowing strange. I was shocked to learn he had an enormous fluid build up on the lungs (which apparently did not show on the periphery of the lungs in the xrays done a week prior. The concern was that it was FIP, triggered by a hospital stay/stress. It was a confusing and alarming time. Try as we might, we could not get ahead of the fluid buildup and he declined to the point that he had no quality of life. I keep wondering what more I could have done. 🙁

  4. Hi, AM Stewart. Thanks for your kind and wise words concerning my kitty. He is due for his next checkup so I will definitely talk to my vet about what sorts of things I need to do, whether to have him tested or wait it out.

    Excellent point about the weight. He weighs 12# now, which seems an ideal weight for his rather big boned frame. His backbone is still quite prominent when I run my hand across it.

    I so want him to live a long, healthy life. Please, God…

  5. AM Stewart says:

    Sharlene, I have some advice as one who lost a Ragdoll to HCM.

    First, talk with your vet about what diagnostic tools are available. If they can do something non-invasive and give you some degree of certainty, it might be worth it. While knowing it might seem more painful, it also arms you with knowledge that might prove helpful later in your kitty’s life. If for instance he’s NOT carrying the gene, you can avoid thinking every ailment suffered by your boy is HCM-related. If he IS carrying the gene, then you can be more aware of his actions and perhaps avoid more serious complications.

    If I had one bit of advice, I’d say make sure to monitor his weight. An overweight cat with HCM is much more serious, and as all cats are notoriously good at hiding illness you might not know he’s in distress until things have gotten pretty advanced. I’m not advocating starving him, but excess weight should be avoided.

    Good luck and don’t automatically assume everything will turn out for the worse. Nothing is guaranteed in life except that your bundle of fluff will bring you much happiness no matter how long his time on earth.

    1. Lisa olson says:

      All cats should be monitored for obesity. It’s the number one killer of cats. Excess weight can cause heart issues, diabetes, liver and kidney problems. My rescue constantly gets cats that have been feed nearly to death. Their owner spoiled them with treats and over feeding (especially with people food). No cat should ever eat people food. Treats are completely unnecessary (unless it’s a little cooked poultry). If you pick up your cat and you feel a firm muscular belly , you’re cat is at a good weight. If you feel flab, your cat is overweight. I have two Ragdolls. My senior is at A great weight. She was underweight when I rescued her. She weighed just 6 lbs. I put two pounds on her by simply encouraging her to eat nutritious meals. She is energetic and healthy at 8lbs. My boy Ragdoll eats everything in sight. He’s 6 years old and weighs 20 lbs. He is a little overweight. We are working on his diet. But he’s a piggie. He was rescued as a stray kitten. I think he was starved

  6. Cindy Bryce says:

    I would not want to know unless there was something they could do about it..love your cat each and every day.. I had 2 sibling Ragdolls . One came down with kidney disease at the age of 6.. I treated India for 4 years.. They told me I would probably only get 1. But I gave her fluids every day..and loved her. I did worry about her sister China getting it also… But so far so good. And she is now 15…I know it’s hard as we love our cats so very much.. But usnt that the best medicine of all?? Stay strong and enjoy!! XO

  7. Thank you, Linda, Jo, and Amanda! I so appreciate you all taking the time to reply to my concerns and also giving your opinions as to what I should do. I tend to think I’d rather not know. I’d say the chances are he carries the gene if his father was found to carry it. His father, incidentally, is three years old and in perfect health. Of course, the breeder has removed him from the breeding program. Question, can anybody tell me what Blue’s breeder meant when she said she has discovered that Blue’s father carried “one copy” of the gene for HCM? And the father’s mother (Blue’s grandmother) also carried one copy.

    What does “one copy” mean – other than they carry the HCM gene?

    Another question…Blue’s half-sister, the one who shared fathers with Blue and died of HCM…was a white/cream-colored blue-eyed kitten. I’m told there is some truth to the blue-eyed kittens being more susceptible to HCM? Is this true?

    My cat is a “blue mink, lynx point, mitted male”. His eyes are sort of an aqua blue/green color.

    Thanks again, everyone. I am leaning toward NOT wanting to know if Blue has the HCM gene. Hope I’m not being irresponsible.

  8. Why bother with a gene test? If he has it, he has it. If he doesn’t, then you’ve spent a lot of money for nothing. He’s not a breeding cat so it’s not important to his “lines”.

    Just make sure your vet knows there is a history of HCM in his family lines and get his heart checked every 6 months, including an ECG annually (or 6 monthly if you can afford it).

    As always, be mindful that his quality of life is the most important thing, not the longevity and try to stop worrying until there is officially something to worry about.

    We all worry about what if, but most of the time they don’t come to anything.

    Enjoy your beautiful kitten. 🙂

  9. Hello

    For me, what is the point in knowing. I would personally enjoy him while he is still young. You can have him get an echocardiogram if you are that concerned. HCM can be present regardless of whether you hear a heart murmur or not. We can only do the best we can.

  10. Hi, let her test thruh ultrasound by a specialist, and do the dna.

  11. Hello there! I have a 13-month-old Ragdoll. His half-sister recently died from HCM, and now I am a nervous wreck that my beautiful boy is going to contract the disease.

    According to the breeder who I’ve been in contact with it is Blue’s (my cat’s name) father who ended up carrying the gene. She was unaware he carried it as she’d been told his line was clear of it. So confusing.

    Now the question remains, should I have Blue’s DNA checked, and if I find he is a carrier, then what? Apparently, just because his father was a carrier doesn’t necessarily mean Blue is. (Am I making sense?) My husband says, “Why do you want to have him checked? If we discover he carries the gene then every time he sneezes you will suspect he’s getting HCM, and you’ll drive yourself crazy.” I think he’s right. Since there is no cure for HCM (other than to prolong their life for a brief period of time), what is the point in my knowing? He is neutered, so he will never impregnate another cat.

    Right now I’m concentrating on a healthy, grain-free diet, and encouraging plenty of play. He is totally full of vim and vinegar, and the vet has never mentioned anything about a heart murmur.

    Thoughts, anybody?

    Nervous Nellie

  12. Fip is nobody’s fold, almost every cat is carrying the carona virus.

    It comes with every age and every breed, the breeder can’t do anything about it, its a nasty and deadly desease that it is, but not to blame on the breeder.

    1. Lisa olson says:

      There is no test for FIP. There is no vaccine . There is a cure for it. It is very expensive, it is a 90 day long treatment, and is very hard on the cat. FIP can develop at any age. Most females are exposed to the virus (coronavirus) at some point. Then it is passed along to their offspring. For some reason that we haven’t figured out yet, the virus mutates in some cats and develops into feline infectious peritonitis. There are two types: wet and dry. Kittens who develop FIP rarely survive. No breeder can guarantee that their cats will not develop FIP. It happens in every breed of cat. Regardless of lifestyle or nutrition. I’ve been in cat rescue for 25 years. I’ve seen purebreds, mutts , inside cats and community cats die from fip. Regarding heart murmurs and anesthesia complications. If your cat has a detectable murmur, the vet can use a different anesthesia drug and monitor your cat carefully during surgery. A large proportion of all cats have detectable heart murmurs. My mother’s Burmese lived 17 years with a murmur. He survived early neuter, teeth extractions and he was felv positive. He died in his sleep.

  13. Patricia Holland says:

    HMC is not the only thing to watch for when you purchase a kitten from a cattery, My Ragdoll is 15 months and was just diagnosed with FIP. I knew nothing about FIP until now. It comes from the mother that carries the carona virus. most kittens carry the virus and never get sick but once in a while it mutates and when it does there is no cure.

    1. Patricia Holland says:

      My Ragdoll is also 15 months and was just diagnosed with FIP. I would think breeders could have a test that shows if there female carries the carona virus. If so they shouldn’t be breeding.

      1. Almost every cat is a carona carrier, so you can’t do anything about it, they get it or they don’t get it, its just bad luck if your cat had it, the breeder can’t do anything about it

  14. Hi DNA testing is not enough! always do a yearly echocardiogram, its much better to do both of them.
    It seems that a lot of breeders around the world only test through DNA.
    In Holland its normal to do both. That’s the best way to get it out of the lines.

  15. Last year around the same time the doctor heard a heart murmur in Zoey. I really didn’t think anything of it at that time. Last week I took her to the vet and a different doctor heard the heart murmur. Today(5/29) Zoey had an echocardiogram done and the results were that the heart murmur is benign. When her heart rate is high you can hear the murmur, but when her heart rate is low it’s absent. But seeing that she is a Ragdoll the cardiologist advised me to have her heart checked a year from now. I’m so relieved, it so worth it. It’s better to know than to worry or stress over it.

  16. AM Stewart says:

    I am not a musician and I don’t play one on TV (a bad Jackson Galaxy reference), but I would be VERY surprised if a six-month old kitten could die of HCM while being neutered. As someone else alluded to earlier, I’d be more suspicious of how anesthesia was administered as well as if there was post-surgery monitoring. Animals are just as susceptible to allergic reactions to medicine, so if possible a pet owner should insist upon observation during recovery.

    As for HCM screening, I’m sure there is no 100% certainty. Much like a DNA test can be taken that will show a human’s predisposition towards certain types of cancer, there are other factors such as environment and nutrition that can play a factor.

    I would hate to think someone would pass up the joy of a Ragdoll’s company for fear of what might happen. Nothing is guaranteed, and the love and contentment of holding my big boy “Panda” more than makes up for the risks.

    1. Janet Knowlton says:

      You are absolutely right!

  17. I am planning n getting a ragdoll kitten and i have just recently heard about this disease in the ragdoll breed. If the breeder that i am planning to get my kitten from does not test for this problem is that a red flag should i take myself of the waiting list or could I get him tested myself? Also do you test the parents & the kitten for this disease or just the parents, how often should your kitten be checked? When these tests are done should papers be provide to the person adopting the kitten (me) for proof that the kitten and parents are HCM free? Sorry for the overwhelming amount of questions just want to be sure my breeder is reliable & my new kitten will live a long healthy life.

    1. Janet Knowlton says:

      All I know is that a responsible and reputable breeder should absolutely be testing for HCM and feline leukemia and a couple others. No exceptions. I am with you…I am a nervous wreck now after reading all these horrible stories. I’ll let the more experienced Ragdoll owners answer the rest. Check out some of the complaints and it is shocking. I would like to know the answer to your questions too.

  18. JudyLyn Fanning says:

    Janet…..not a stupid question AT ALL!!!!! My six month old male kitten, who did NOT have a heart murmur or any signs of distress, DIED in recovery at six months old, after being neutered. It was shocking and very, very sad. I saw the paperwork where both parents tested “normal/normal” for HCM. My vet did a necropsy to confirm cause of death. I will be taking my other two kittens to Auburn Vet School Cardiologist Specialist before I have the youngest one neutered. The other kitten that was being neutered at the same time, did not have any complications…..they had different mothers, but the same father. The vet said it may have skipped a generation or just been a fluke. I was devastated.

    1. Janet Knowlton says:

      That is just awful. I am so sorry to hear this. I can’t imagine how devastated you must have been. I am now wondering why I want to get a Ragdoll at all if they are this fragile! Are they really this fragile? I am on a waiting list for a kitten that is from a breeder in Sacramento who seems very good and diligent and tests her cats for HCM and feline leukemia. I am really interested in who your breeder is as I looked at a couple in Auburn and stayed away from one. Would you mind telling me? if not on this site, you can email me at knowltons4@att.net. I have had cats (humane society rescues) all my life and never dealt with these kinds of problems…just the typical old age. I also am learning about all the horrible breeders out there that do not test at all and sell sick kittens and then they later die. These people should be sit down…but that’s another story.

      1. Janet Knowlton says:

        sorry “shut down” not sit down!

      2. Melissa B Keefer says:

        Testing for HCM does not prevent it!! We test for one gene in Ragdolls. There are over 100 genes in people which are responsible for HCM. Anyone who tells you it cannot happen is either not educated about the disease or not being honest. Please educate yourself instead of blaming the breeder. Light blue-eyed males of ANY cat species are more likely to suffer from HCM, we don’t know why, but may be gene linked. It is not usual to see symptoms before the death occurs, but you may. The necrotopsy of a cat who died from HCM looks very similar to the necrotopsy of a cat who suffered an anesthetic accident. This lets vets off the hook with a very convenient excuse. Ragdolls are not “fragile.” We just happen to be one the groups more active in testing. ALL cats are susetible to the disease. Persians, Maine Coone and Ragdolls run a higher incidence in the pedigree population. No one is looking for it in the domestic short hair population!

        1. Janet Knowlton says:

          I was only pointing out the breeders that do no testing at all. Thank you for all the information…not that it makes me feel any better! Just like anything else, the horror stories are the ones that are generally posted and not all the great stories. I have to keep that in mind.

  19. Janet Knowlton says:

    This is probably a very stupid question but if both parents test negative for HCM, is there any way the kitten could get this?

  20. AM Stewart says:

    As someone who lost a kitty to HCM about a year ago, I am painfully aware of the symptoms and treatments available. I used Lasix, Enalipril and VetMedin (which is normally a canine drug) over an agonizing three month period. The costs of the drugs weren’t the problem – it was having the fluid drained around the lungs and all the diagnostic tests that ran the bill into the thousands. From a strictly unemotional perspective it wasn’t worth it, but I found that I just couldn’t let him go without trying something.

    In hindsight I question whether I held on too long, but since I’d only had him for three years (he was a stray who showed up on my front door step) I was devastated by the thought of losing him. I’ve lost cats who died of age-related issues, but over a span of years it gets easier to accept. Not easy mind you, but I’ve been lucky to have cats that lived near two decades in most cases.

    So if you have a kitty that is diagnosed with HCM, just be realistic on the expected outcome. Be sensitive not only to your own feelings, but also those of your suffering pet. I hope nobody else here gets a diagnosis of HCM for their cats, and I’m just glad my newest Ragdoll was found HCM-negative as a kitten.

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