Drugs for cat with restrictive cardiomyopathy

Re: Drugs for cat with restrictive cardiomyopathy

Rajat — Wed, 22 Aug 2012 23:49:31 GMT

Hi sarah

How strange! So I take it the cat is in sinus rhythm at that rate when it had an ECG....cats just do their own thing don't they?

I had an RCM kitty just a few days after yours. It wasn't clinical yet but I have been tracking it for a little while (previous murmur was not due to RCM -SAM-e/DLVOTO- so it had echos previously) - like your cat it had a great response to pmobendan. The cat is eating better sleeping less and generally much happier and active. I am waiting to see if its renal values decrease (it has been in CRF for 2 years or so) as they went up after it developed RCM.First time I've used pimo pre clinically in a cat but seeing the systolic and diastolic dysfunction I thought maybe worth a try

Best of luck with your case n thanks for the update

Rajat

Re: Drugs for cat with restrictive cardiomyopathy

Sarah Keir — Wed, 22 Aug 2012 17:51:11 GMT

Hi Rajat,

No arrhythmia on ECG! But when the cat was out of the kennel later in the day, a dog walked past and it too fright and ended up lying down for about 30secs - colour good, no mouth breathing, slight increase resp rate, grabbed a stethascope and head sounded arrhythmic but once got the ECG was normal again!

But started the cat on pimobendan and resting heart rate is now 110-120bpm. Saw the cat back today and doing very well. If it runs down the garden then it lies down for a short time then carries on as normal. Bloods show mild azotaemia so going try and reduce the frusemide dose.

Sarah

Re: Drugs for cat with restrictive cardiomyopathy

Rajat — Wed, 22 Aug 2012 17:22:00 GMT

Hi Sarah

Curious as to what your cats ECG showed? Did it confirm a 3rd degree AVB?

Re: Drugs for cat with restrictive cardiomyopathy

Rajat — Sat, 11 Aug 2012 16:19:03 GMT

I agree with your point there should be some signs of forward failure. The classic triad of feline shock (not just cardiogenic) as you know would involve hypotension,hypothermia & bradycardia. This cat had bradycardia and CHF and it is not unreasonable to assume they are related either by the cat's shock syndrome, or as may be the case here third degree av block.

I would counter, tho, that it is far less common to have cats with 3rd degree AV block present in CHF, rather, they present idiopathically (HR low in consult room ii.e. 120 or less) or occasionally for vague lethargy/syncope.

So while any cat with low HR should get an ECG (and hence pick up the 3rd degree AVBlockers amongst them) generally cats with CHF in my experience and according to emergency texts are the ones who present with CHF and low HR. And when there is low HR there is usually low output (decompensatory shock) as well and hence the hypothermia.

Hence my assertion that [quote user="David Mills"]but if a feline patient presents with CHF and bradycardia technically it is in cardiogenic shock. [/quote]

I accept however, I have assumed some of the un-presented clinical signs (eg BP on admit, temperature) - sorry!

Re: Drugs for cat with restrictive cardiomyopathy

David Mills — Sat, 11 Aug 2012 15:44:09 GMT

[quote user="Rajat"]

Lol well if it is running around agreed shock is unlikely but if a feline patient presents with CHF and bradycardia technically it is in cardiogenic shock.

[/quote]

Not necessarily. It could simply be in CHF with concurrent heart block. The definition of cardiogenic shock must include, surely, signs associated with low output failure - of which CHF may/not be one - not simply CF and bradycardia. Moreover, diagnoding cardiogenic shock in cats via HR is notoriously unreliable - many in fact will be tachycardic.

Re: Drugs for cat with restrictive cardiomyopathy

Rajat — Sat, 11 Aug 2012 12:45:01 GMT

Lol well if it is running around agreed shock is unlikely but if a feline patient presents with CHF and bradycardia technically it is in cardiogenic shock.

From what you describe the patient is no longer in CHF- If the bradycardia persists despite congestion clearing I'd workup the bradycardia.The ECG is a good idea- third degree av block would not be uncommon, had one just 2 days ago! They are usually asymptomatic in cats. Would be number 1 rule out if your cat had not presented with CHF and concurrent bradycardia, but if bradycardia is persistent then it is suspicious.

Pls keep us posted on what u find!

Re: Drugs for cat with restrictive cardiomyopathy

Sarah Keir — Sat, 11 Aug 2012 11:54:51 GMT

It is not in shock, that much I can tell! Running around the prep room, rubbing against my legs as I speak, normal temp. HR up to 100bpm this morning but no variability still. I am going to do an ECG later as a clinical scholar at RVC replied to my message and suggests 3rd degree heart block is common in cardiomyopathies of cats. Started him on Vetmedin this morning (after measuring the heart rate).

Sarah

Re: Drugs for cat with restrictive cardiomyopathy

Rajat — Sat, 11 Aug 2012 09:57:57 GMT

Hi Sarah Ok so the cat is severely bradycardic as yu know at that rate- this is a sign of shock in cats- they tend to get the triad of hypotension hypothermia and bradycardia in shock, one can assume this is likely cardiogenic shock. So the bradycardia is not a normal physiological response i.e. to allow increased relaxation, rather it is an abnormal one indicating decompensatory shock.

Tough to treat other than gentle rewarming, diuretics for congestion - no fluids, unless giving hypotonic fluids vv cautiously to replace free water deficit (I've only done this 2-3 times) but if hypotensive (as it likely is) dobutamine CRIs often help to transition them to a stage where their cardiogenic shock is under control and their HR come sup and they can come off it. Pimo kicks in pretty quickly but I worry about poor stomach/gut perfusion poor absorption and distribution in shocky cats so prefer dobutamine IV, you do have to be cautious in cats re side effects dose rates 1-2.5ug/kg/min.

David is right in that RCM carries the poorest prognosis as we currently know from all the feline myocardal diseases.

Re: Drugs for cat with restrictive cardiomyopathy

David Mills — Sat, 11 Aug 2012 00:43:15 GMT

Pimobendan has been used in a fair few cats - there a recent case series of 170 cases with no obvious negative effects on survival though no positive effects could be demonstrated. The st in rcm is terrible in any case so may be worth a go. All sorts of arrhythmias are possible though 80 is low. Treatment for bradys is often pointless but slow heart rates are still compatible with life in cats in the main.

Re: Drugs for cat with restrictive cardiomyopathy

Sarah Keir — Fri, 10 Aug 2012 21:33:47 GMT

Yes, the right side was huge too. And no, I meant 80 bpm NOT 180! I haven't put the ECG on yet but this is tomorrows job. I'm not sure why it would be this slow but I would of thought that in this case it would help as it helps the ventricle to have to fill fully.

Cardiology is not my strongest area so all your comments are most gratefully received.

Sarah

Re: Drugs for cat with restrictive cardiomyopathy

Martin Atkinson — Fri, 10 Aug 2012 19:34:01 GMT

I would add in pimobendan as well, dose is double that for dogs so average will be as Raj suggests. I tend to still use aspirin as I have no experience of clopidrogel. I also find the dose of frusemide recommended generally for cats is too low so don't be scared to go for 20mg bid or even tid if you're still getting effusions.

Re: Drugs for cat with restrictive cardiomyopathy

Rajat — Fri, 10 Aug 2012 19:04:35 GMT

Hi Sarah

Poor kitty- one truly nasty disease. Was the RA huge too? Sounds like it may have the endomyocardial form of RCM or other variety but the management is going to be pretty similar.

did you mean 180bpm?

Personally I don't use Diltiazem as you may know if you read one of the other posts, but Pimobendan is very useful and has some lusitropic properties too. Mostly use half of 1.25mg bid. On empty tummy preferably an hour before food - absorption is reduced with food.

If not already doing it try getting the owners to count sleeping resp rates, they should be <30-35 in cats with controlled CHF and monitoring trends can 'catch' these kitties before they go into full blown CHF again.

Another thing which may add more bang to your anti thrombotic buck is the addition of Clopidrogel one quarter of 75mg daily. Is a stronger anti platelet drug than Aspirin. You can use them together (and I would here if its LA is 3 cm!)

Best of luck

Raj