Heart murmurs in cats

[beowulf]

What is the going consensus about how to treat, or what to expect? I don’t have much info ATM… Dropped off HC at the vets’ last night after work, because I noticed a change in behavior - she started hiding two days ago. SO thought it was because of all the awful construction we’re having at night, but I’m not so sure. If I pull her out from her hiding spot she is bright and interactive. She’s nearing 11 so I thought it best to just bring to the vet and have them give her a once-over. I asked them to pull bloodwork and they noticed an obvious murmur. They pulled some sort of heart tissue (? this was over the phone, I don’t have the exact term, sorry) diagnostic and said they’d be back with results in 24-48 hours. They are going to test for hyperthyrodism and a few other diseases with the blood panel.

I’m assuming my next step is likely a cardiologist for an echocardiogram… Anyone else been through something similar?

[OzarksRider]

Hyperthyroidism definitely can cause heart issues in cats, and your cat is at the age where this is certainly a possibility. The good news, if it is hyperthyroidism, is that it can be completely cured with radioactive iodine or controlled with methimazole. Usually, the heart issues will resolve once the hyperthyroidism is under control unless there is some underlying condition. I once had a hyperthyroid cat that presented with cardiac symptoms. She was treated and cured with radioactive iodine. Her heart issue resolved and she lived a completely normal life for several years until she was euthanized at age 15 for a squamous cell carcinoma in her jaw.

[CHT]

As @OzarksRider mentioned, it may be related to hyperthyroidism. A now passed on kitty had hyperthyroidism and a subsequent heart murmur. She was only semi tame or would would have done the radioactive treatment (we would have to fly her out of province to get it done). We did the methimazole, but she didn’t respond well to the medication (a current cat is also on methimazole and doing great). A client/friend has a cat with a heart murmur on its own, but aside from making general anesthetic more risky, she hasn’t had to do any treatments/special care.

I hope your kitty is ok

[shiloh]

Jingling for your kitty.

My Ollie cat that recently passed was diagnosed with hyperthyroid related cardiac issues. They said it was HCM. They kept pushing me to do cardiac ultrasound and see cardiologist but as that was $$$$$$ and I declined. Plus, he had other issues and it wasn’t going to improve the diagnosis or make him better so what was the point. The ultrasound would have been $600-ish and the cardiologist $500-something for a visit. He had high bp so was prescribed amlodipine which did help and was well-tolerated. I can’t remember whether the vet told me murmurs were common or uncommon in cats. Common in horses I know but but can’t remember if cats were.

Again, hoping for the best for your kitty!

[Ponycatraz]

Current cat and last two have had heart murmurs that developed as they aged. 2 were not treated but just watched. One made it to 19 (lung cancer) the other is 20 and going strong.

The third had hyperthyroidism that was treated with radioactive iodine and he also made it to 20(bone cancer). No other treatment for his heart.

So at least for my cats the vet didn’t recommend treatment for their murmers and they lived full lives.

[JB]

2 years or so ago - BC Before COVID because I was in the vet room - 2 of ours had a hear murmur show up at their regular yearly checkup. Blood was pulled on both to check all kinds of things, and all came back clear. Every 6 months they’ve had re-checks. 1 has remained the same, 1 has diminished.

However, they are both slightly past mid-teens (14 and 15 when each was first discovered), so maybe that’s more age-related?

Jingles for your girl, 11 is still quite young!

[Maythehorsebewithme]

Friend had a cat diagnosed with heart murmur at age 8. Vet prescribed daily medication, I don’t know what. Friend realized that the fight to get the medication into the cat would be ridiculously difficult, and could make matters worse. She opted to let nature take its course. Nature is still taking its course, cat is 18.

[CdnRider]

The test is probably a cardiopet proBNP, basically it is a non-qualitative test to indicate if their is excess stretch on the heart. My vet likes this test since an echocardiogram (gold standard) is financial not feasible for a lot of owners.

My cat was diagnosed with a HM at age 7. I did 3 echos between 7 and 11 years old. His murmur was was due to hypertrophic cardiomyopathy and never worsened significantly, his last echo was with a cardiologist and she recommended routine checks, monitor for symptoms of heart disease. He died at age 11, only 3 months later because of acute kidney disease.

Most cats with heart disease don’t present with a murmur but still have hypertrophic cardiomyopathy. It is vastly underdiagnosed because it usually can only be diagnosed by an echo. Which is were the cardiopet proBNP can be handy. This is different than dogs because they tend to get mitral valve disease that progresses quickly to heart failure or DCM that can be diagnosed via x-rays, although an echo is still gold standard for all heart related issues.

If the rest of your blood work comes back normal (specifically the T4), I would imagine the hiding is related to environmental causes and the heart murmur was an incidental finding as was my cats on his routine annual exam. Probably a good idea to monitor blood pressure on a routine basis as cats can have primary hypertension that can cause murmurs. Besides blood pressure meds and thyroid meds if underlying hyperthyroidism is involved, I can’t even think of any cats I’ve seen treated for heart failure because of a related heart abnormality and I’ve also worked emergency medicine.

Good on you for working it up! And goodluck with your cat.

[beowulf]

Thanks all. I’m sorry for those who lost their kitties (either related or unrelated to the heart murmurs).

Bloodwork and the heart stretch test came back normal. No hyperthyroidism.

We have a follow up appointment with a cardiologist on the 12th.

Kitty seems okay, still being hidey and construction has moved off.

[sascha]

I have a middle-aged cat who developed a heart murmur a few years ago out of the blue, no easily identifiable cause. We opted to try weekly injections of B12 which are very easy to do at home. A couple of months later the murmur was gone so we didn’t even get into further diagnostics on him. For once I got lucky with a cheap and easy fix.

[JB]

@CdnRider

The test is probably a cardiopet proBNP,

YES, thanks for that, that’s what was run for mine. IIRC the vet was looking for toxoplasmosis and a couple other things, none of which came back.

[GoodTimes]

I’m a cardiac sonographer (human) and I strongly encourage anyone who is told that they or their pet have a murmur to get an echo.
We get referrals all the time for murmurs and the echo is totally normal. Some doctors and vets just aren’t very good at identifying them, or the sound isn’t actually coming from the heart.
We also get people coming in with severe valve disease, etc. They’ve obviously had murmurs for years and no one ever noticed it.

Murmurs that are the result of valve disease do not just go away.
A murmur that is the result of a septal defect may get quieter - this is not a good thing, it means the pressures between the left and right are equalizing and could eventually result in severe pulmonary hypertension and right heart failure.
A murmur that is the result of an obstructive hypertrophic cardiomyopathy can be louder or quieter depending on BP, HR, blood volume, and contractility. ie murmur may be nonexistent at rest, and turn into a significant systolic murmur with exercise/Valsalva maneuvers.

An echo is the gold standard.

[CindyCRNA]

Pooter lived to be 21 with a 3/5 murmur for at least 3-5 years.

[PonyApocalypse19]

I had a cat with a heart murmur 4 years ago. I believe it was caught during a routine yearly exam (I don’t remember too much now). He was young - only 5 at the time of diagnosis. He saw a cardiologist after his ultrasound and was diagnosed with congestive hear failure. He was put on a couple different medications- a beta-blocker, a diuretic, and a blood thinner. He was good about taking pills, but had to have medication twice a day every day. Towards the end he would just eat the pills off the counter - he was a goof. He passed away while I was at work about 6 months after diagnosis. He started having dizzy spells which were probably ischemic events a couple months before the end.
I don’t want to scare you, but just wanted to relate my experience with it. We don’t know why the heart murmur never showed up before. So it could have been something genetic that became more pronounced as he aged - he was a mainecoon and his full sister developed cancer around the same time. (I still have one full sister left and she’s quite spunky and very healthy)
I hope your kitty has a good prognosis and it’s a manageable condition.