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    heart murmur in older cats
    gingert posted:
    My two cats were both recently diagnosed with stage 1 murmurs, what would be the next step? They were taken to the vet for dental exams. My female cat is unsteady and losing her balance, blood work (Antech basic wellness) we were told was fine. Should we do blood work for hyperthyroidism?
    srstephanie responded:
    Hi gingert,

    How old are your "older" cats? It would probably be a good idea to do a full "senior" blood panel which would include checking their thyroid values (T4). A blood pressure check might also be a good idea because hypertension (high blood pressure) can also cause heart disease ... though getting an accurate blood pressure reading on cats is tricky.

    I would also want to pursue what is causing your female to be "unsteady and losing her balance". That could be something else going on as well.

    The only way to know what is causing the heart murmur is by doing an echocardiogram (ultrasound of the heart) ... preferably by a cardiologist (which is expensive) or at least by an experienced Internal Medicine or Feline Specialist. Some causes of a heart murmur are no problem ... but the concern is to check for hypertrophic cardiomyopathy (HCM) which is a genetic disease that often doesn't develop until middle age or later. It causes a thickening of the left ventricle of the heart which thickens inward so that the space in the ventricle becomes small and difficult to pump the blood out. It is a progressive disease, though the rate of progression is extremely variable ... so that in some cats it never becomes a health factor, though in others it can lead to heart failure and death. Are your cats related? HCM is generally considered a genetic disease, so related cats have a higher risk if one of the parents has the gene.

    I don't know that HCM is a factor with your cats. But if you want to learn more about it, I highly recommend a website that was done with the help of Dr Mark Kittleson (of UC Davis) who is THE authority on feline HCM. He retired last year but spent most of his career researching HCM. This website was written for pet owners and gives info from the top expert, explained so that non-professionals can understand. Here is the website address:

    If there is thickening of the heart that is secondary to hyperthyroidism or hypertension ... then, when those conditions are treated, the heart will usually return to normal.

    Your vet will guide you on what to do and when. But it is probably a good idea to follow up on the heart murmurs ... and also the balance problem your one cat has.

    Good luck,
    Stephanie in Montreal
    Drew Weigner, DVM, ABVP responded:
    Technically speaking, a heart murmur is caused by turbulence as the blood flows through the heart. That doesn't necessarily mean your cats have heart conditions, but that's the most serious cause and needs to be determined before anesthesia. There are many other things besides heart disease that can cause murmurs including anemia, hypertension, fevers, etc.

    If the preanesthetic lab tests didn't include a thyroid profile, there are probably other needed tests missing, so a full diagnostic workup needs to be done on both cats. They also need to have their blood pressure checked. If everything comes out normal, an ultrasound of their hearts will tell you if they have a heart condition. If that's normal, they have "innocent murmurs" and it should be safe to proceed with their dental cleaning.

    Drew Weigner, DVM, ABVP
    The Cat Doctor
    Board Certified in Feline Practice
    jselleck replied to Drew Weigner, DVM, ABVP's response:
    Hi guys, I couldn't help but notice your posts. We took our cat Jack to the vet this morning for his "yearly" and were also told that he has a murmur among other things. He's either 12 or 13 years old, we're not sure of his age because he was a stray taken in by a friend's mother and then given to me when I lived in Indiana. Jack has an interesting medical history to begin with. We affectionately call him "Goat Kitty" because he loves to eat weird things. Including the silver safety tab off a ketchup bottle, carpet fibers, and that's just the tip of the iceberg. He's constantly hungry no matter how much we feed him, loves to scrounge food off our plates, and when he sleeps half the time, he sleeps like he's in a coma or something. My husband has on numerous occasions picked him up from where he was sleeping and moved him to someplace else in the apartment. He'll wake up with the stupidest look on his face, but he'll actually sleep though being moved. He also loves "upside down belly rubs." Were my husband will hold him upside down and I'll rub his belly. It's so funny, but he loves it!!! I strongly urge you to have your vet check your animals' thyroid levels. Mine came right out and said that hyperthyroidism in older animals can not only cause heart murmurs, but weight loss and other "bad" stuff as well. Good luck finding out what's wrong with your babies!!!
    gingert replied to jselleck's response:
    Thanks! Jack seems like a great friend! Thyroid ok on both cats. I think unsteady cat has vestibular disease so here we go!
    gingert replied to srstephanie's response:
    Thanks for the reply, heart murmur is on watch right now, unstable cat, I think, has idiopathic vestibular disease. Going to a new vet tomorrow. My babies are 11 yrs old. Previous vet does not have my confidence.
    gingert replied to Drew Weigner, DVM, ABVP's response:
    Thank you for the reply, thyroid test was included and both cats were fine, well within range. Female had her teeth cleaned, murmur was not mentioned until follow up after cleaning. She is not well after surgery, symptoms include stumbling, head tilt, shaking head weak legs! I think she has idiopathic vestibular disease. This has happened over 2-3 week period of time after surgery. Going to new vet in am.
    jselleck replied to gingert's response:
    Good luck with new vet!!!! Hope you find something soon. Never fun when one of our human or animal babies is sick

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