Is a persistent gallop rhythm (triple beat) In dog/cat always a sign of pathology?

RE: Is a persistent gallop rhythm (triple beat) In dog/cat always a sign of pathology?

Nuala Summerfield — Thu, 16 Apr 2020 12:40:37 GMT

Hi GrooveJet and Dave

Great question about gallop sounds. Particularly in cats, heart murmurs get a lot more attention and yet gallop sounds are often more likely to be associated with significant underlying heart muscle disease (cardiomyopathy). I would tend to agree with Dave that in a cat with no respiratory symptoms, without an echo to diagnose the type/extent of cardiomyopathy present, or thoracic radiographs to assess degree of cardiomegaly, clopidogrel would be the only drug I would recommend.

If there was also an increased resting RR or RE reported, then loop diuretics (ie. furosemide or torasemide) would be indicated. Every effort should be made to maintain the cat on the lowest effective dose of loop diuretics to minimise the risk of renal complications and diuretic resistance. Owner-counted RR when the cat is calm and resting or ideally sleeping at home is a great way to remotely monitor CHF control. Owners like to feel involved in the management of their pet and it tends to increase compliance. You can use a video call to show the owner how to count RR and then you can use the resting / sleeping RR trends as a guide to help you taper the loop diuretic dose to the minimum effective dose, so RR stays stable and < 30 breaths / min. There are several easy to use smart phone apps you can ask your owners to download to help them count and record RR at home. Especially now with the C-19 restrictions and the need to remotely manage a lot of our patients if possible, involving your owners in home RR monitoring makes a lot of sense to try to avoid these cases deteriorating and becoming emergencies.

I would also be reluctant to use other cardiac meds in a situation where I could do no further work-up.

Hope this helps

Nuala

RE: Is a persistent gallop rhythm (triple beat) In dog/cat always a sign of pathology?

Dave Dickson — Thu, 16 Apr 2020 11:09:29 GMT

[quote userid="11901" url="~/001/veterinary-clinical/small-animal/cardiology/f/expert-help/29028/is-a-persistent-gallop-rhythm-triple-beat-in-dog-cat-always-a-sign-of-pathology/221775"]sadly, this does happen in 1st opinion practice[/quote]

Ha! I may be in referral practice but I'm not totally out of touch...

In some respects, feline cardiology is easy. We know two drugs work: frusemide and clopidogrel. After that, it's pretty much open to debate and nuance and robust opinion.

So, in a cat with a gallop sound but who isn't breathless, and for whom you can't do any tests, I think starting clopidogrel (Summit 18.75mg SID, NOT the human generic tablets) is likely to do more good than harm. If they won't take clopidogrel (some won't) then 1/4 x 75mg aspirin twice a week is reasonable.

If they are breathless then I'd give frusemide or torasemide, to clinical effect.

After that, I'd need more information about the heart disease to know how to treat. ACE-inhibitors may work but we have no evidence that they do, and some that they don't. Spironolactone may work, but the evidence is weak and certainly not good enough to make me want to put cats on it without knowing more about them. Pimobendan may work in a subset but they need checking carefully as it has potential to do harm - I've seen cats become hypotensive on it. There is unpublished data suggesting it harms some cats too so we need to be careful with it.

Hope that helps! See what other cardiologists think too - the above is just my opinion.

Dave

RE: Is a persistent gallop rhythm (triple beat) In dog/cat always a sign of pathology?

Miriam Lodewyks — Thu, 16 Apr 2020 10:31:38 GMT

Thank you Dave!
In the event that there is absolutely no interest in any further diagnostics of any kind, but the client is able to afford a modest amount of money monthly for some form of treatment (sadly, this does happen in 1st opinion practice): what would be your “go-to” drugs and in what order (ie. Most effective, cost-effective option)?

RE: Gallop rhythm

Dave Dickson — Fri, 10 Apr 2020 08:53:38 GMT

Hi GrooveJet

A gallop sound (sometimes called a gallop rhythm) is nearly always abnormal. In the studies done in cats, 90% of cats with a gallop sound had significant disease. The same is probably true in dogs, though in dogs gallop sounds are much less common. They usually point to diastolic dysfunction, which is nearly always caused by some form of cardiomyopathy.

In dogs, another cause of having 3 heart sounds is to have something called a split S2, where the second heart sound (a combination of aortic and pulmonic valve closure) is divided, usually because the pulmonic valve closes late due to pulmonary hypertension.

In practice, my advice is that any dog or cat with a gallop sound needs an echo. If funds are limited, then run a proBNP first (snap proBNP in cats as it's cheaper, quantitative proBNP in dogs). If these are normal, the animal is probably fine (not 100% accurate, but not far off). If the proBNP is elevated, they need an echo. If echo is not available then some good quality chest radiographs (2 or 3 views) are next best.

The reason I avoid the term "gallop rhythm" is that many people misinterpret this to mean the animal has an arrhythmia and therefore think an ECG is the next test. ECGs are very poor at detecting subclinical heart disease (even in CHF, many dogs and cats will have a normal ECG), so it's an insensitive test and if funds are limited, I spend the money elsewhere.

Hope that helps :)

Dave