Neo mercazole

Re: Neo mercazole

Rajat — Wed, 20 Jun 2012 17:26:22 GMT

Thanks Martin. And sorry Katherine, didn't mean to hijack your thread (was also gonna suggest we open a diff thread or chat elsewhere today, MArtin got there first )

Re: Neo mercazole

Martin Atkinson — Wed, 20 Jun 2012 10:07:21 GMT

[quote user="Rajat"]

Martin, watching the England match so will reply more later, but can I ask where/if your study was published or written up, I would love to have a read. I am not attacking you, please do not misunderstand, but I do dispute thyour e assertion that NTProBNP can replace echocardiograms or is a sensitive way of tracking the severity/progression of feline cardiomyopathies based on what we currently know. My understanding of the literature as presented above does not indicate this but am happy to stand corrected.

WOuld love to hear more of your experience and data if you have it published

Best

Raj

[/quote] As we've hijacked the thread and everyone else is probably fed up with me beating on about this I've replied via a message.

Re: Neo mercazole

Rajat — Tue, 19 Jun 2012 19:56:08 GMT

WOuld love to hear more of your experience and data if you have it published

Best

Raj

Re: Neo mercazole

Martin Atkinson — Tue, 19 Jun 2012 19:38:48 GMT

Wow Raj where do I begin to defend myself? With due respect I have inwardly digested the 2008 Connolly study and referred to it in previous communication to the profession on this subject but it was aimed at measuring NTproBNP in cats with hypertension due to renal disease not cardiac disease. If you interpret their results they only showed significant increases in cats with a combination of severe renal failure and hypertension and those increases were not as high as those that are produced in cardiac failure in my study so it is IMO possible to differentiate between cats with heart failure and those with just CKD. My figures differ from those given by Idexx for interpretation in that I did not find any cats with symptoms of cardiac disease below a level of 357pmol/l but I would respect their figures of 100-270 as being a cut off above which I would be doing further investigations. Cats with levels above 357 all had cardiac disease with some symptoms of failure i.e combinations of fatigue, arrhythmias, FATE and CHF. The severity of these symptoms rose in direct correlation with the severity of symptoms with the most sick having levels in excess of 1000 up to 1500. The additional diagnostic techniques used in my study included echo, ECG and X-ray (although not all 3 in every case) but as previous suggested every single cat which had symptoms of cardiac disease (and a BNP over 357) showed correlating diagnostic features on at least 2 out of 3 of these techniques. Interpret this as you like, it was not controlled nor peer-reviewed, I did it primarily for my own interest in practice because no-one else had documented the correlation of NTproBNP with feline cardiac disease at the time and I wanted to share it with others. I also have looked at some other studies some of which didn't use Cardipoet which is IMO the gold standard for this test and even those which did prior to spring 2010 when Idexx's ranges and collection protocol was changed are potentially flawed because collection and handling technique were not as controlled and were thus prone to false negatives.

In relation to the use of NT proBNP for screening cats with cardiac murmurs, all the cats included in my study were included because they had cardiac murmurs. Like Connelly I found that of those one third had NTproBNP levels that indicated cardiac disease and two thirds didn't and this also correlated with other clinical signs and tests. I would always advise owners of cats with a murmur and a raised NTproBNP to be referred for echo but I am happy in my own mind that I can rely on NTproBNP where the client doesn't for one reason or another want to go for echo and, because the onset of cardiac failure in cats can be so catastrophic, I would even stick my neck out so far as to say that I would consider pre-emptive treatment in all asymptomatic cats with NTproBNP levels over 350. Of course someone will now say there is no evidence to show pre-emptive treatment has any influence on the onset of heart failure in cats because no-one has done the research, I for one don't want to take the chance.

As to regards cost Idexx charge £23.60 for Cardiopet - I don't know how many of those you can do for one echo.

Re: Neo mercazole

Rajat — Tue, 19 Jun 2012 16:17:14 GMT

[quote user="Martin Atkinson"] I suspect you're getting your lines crossed with the usefulness of NTproBNP in dogs and cats.[/quote]

With respect, I don't think I am.

A study from 2008 did find elevations in natriuretic peptides cats with heart disease, and found that NTproBNP could differentiate control (non cardiac cases) from study cats (heart disease+ CHF) and was significantly different between CHF and non CHF cases (both with heart disease) - the sensitivity was excellent but specificity was 89% leading to false positives. The authors conclude that it would be prudent for positives should be followed up with an echocardiogram. (Connolly et al, 2008, http://onlinelibrary.wiley.com/doi/10.1111/j.1939-1676.2007.0024.x/full#t3).

A subsequent study investigated this further (screening for HCM ) and found NTProBNP to be only elevated in cats with severe HCM (Hsu et al 2009, http://www.sciencedirect.com/science/article/pii/S1760273409000095). It was not elevated in cats with mild to moderate HCM.

It has been investigated for its efficacy in differentiating cardiac from non cardiac dyspnoea in cats and was found to accurately differentiate CHF from primary respiratory cases of dyspnoea (Fox et al 2009 http://www.sciencedirect.com/science/article/pii/S1760273409000022, Connolly et al 2009 http://www.sciencedirect.com/science/article/pii/S1760273409000101). Interestingly, the first study contradicts your 'internal' study' - because it was found that NT pro BNP in cats did not correlate with radiographic heart size, left atrial size, left ventricular dimensions or the E/E_a ratio (estimated filling pressures using DTI) - while the 2008 Connolly study did find correlations with La/Ao and more so with E/E'.

You say 'other methods of determining cardiac failure' - what other methods are you using? My limited knowledge indicates CHF being a diagnosis of thoracic radiography, also one can make a pretty good educated guess with astute observation, history, exam and echo without chest rads in many many cases.

A good review of biomarkers in feline caridomyopathies by David Connolly has been published in Vet clinics of north america 2010. I quote a paragraph (as I am feeling lazy and tired having only had 4 hours of sleep last night...on call.. long story..)

" Common problems encountered in feline cardiology include how to interpret the presence of a systolic heart murmur in an otherwise healthy cat or how to definitively rule out cardiomyopathy on physical examination. In a recent study, heart murmurs were detected in 16 out of 103 (15.5%) apparently healthy cats and further assessment identified cardiomyopathy in 5 of the 16. Furthermore, in the same study 11 out of 16 cats with cardiomyopathy did not have a heart murmur.⁶³ Similarly, based on our present knowledge it is not possible to recommend measurement of NT-proBNP as the sole method of screening cats for silent myocardial disease. The results from the feline studies outlined in Table 1 show some divergence with regard to the ability of NT-proBNP to identify asymptomatic cats with cardiomyopathy. Therefore, if a cat has an elevated NT-proBNP concentration and no other comorbidities, such as severe (but not mild or moderate) CKD or systemic hypertension,²⁵ further cardiac evaluation, such as echocardiography, should be performed whether a murmur has been detected or not. If a murmur is detected in a cat with normal circulating NT-proBNP concentration it is still not possible to completely rule out cardiomyopathy and so an echocardiogram would be recommended."

So if a cat has a murmur, no other co-morbidities, and a high NTPro BNP there is a good chance it will have cardiomyopathy. Then what? Is it HCM or RCM or other? How bad is it? What is the risk for CHF? Does it have DLVOTO? Does it have remodelling? What is the LA size? Unfortunately, we

need echo for these details..!

Also from the manufacturer :

Table 3. Current recommendations from the manufacturer (Cardiopet proBNP) for the interpretation of the feline NT-proBNP assay

NT-proBNP Concentration (pmol/l)	Interpretation
<50	NT-proBNP concentration is not elevated. Heart disease is unlikely.
50–100	NT-proBNP concentration is elevated. Heart disease may be present. Consider an echocardiogram or repeating test in 3 months if clinical suspicion persists.
100–270	NT-proBNP concentration is elevated and consistent with heart disease or heart failure. An echocardiogram is recommended. If signs of heart failure are present, a chest radiograph is also recommended.
>270	NT-proBNP concentration is significantly elevated. Congestive heart failure is highly likely. Where clinically stable, a complete cardiac workup should be performed. Where clinically unstable, assess whether therapeutic stabilization is required if additional diagnostics prove stressful to the patient.

Seems, regardless of findings, a cardiac workup is reccommended unless very low, in which case heart disease is unlikely, but not impossible. In my opinion this test more or less a waste of money, and time. An echo takes 20-30 minutes, is quick, results are instantly available, is accurate, gives you valuable information you can track and is not dependent on 'sample handling'..and so on.I can see why it is useful as an initial test, but iIMHO, n no way does this replace an echocardiogram!

[quote user="Martin Atkinson"]Perhaps the fact that I don't have echo may influence my reliance on this test and the fact that those who do prefer to dismiss it may be of significance![/quote]

I have access to both echo and NT Pro BNP. I choose not to use the latter. I could, it would increase the practice turnover, I could use select studies to somehow justify its use...but I cannot, because it doesnt help me or the patient..I can see how it would help as a bedside test to track patient progress, especially during OOH/night time, as it could give you a quick answer especially with someone not confident at echo.

Not having an US machine (or one with echo capabilities) doesn't mean you can't refer for this, right?

[quote user="Martin Atkinson"]It is a lot cheaper, more convenient and easier to repeat serially with increasing values giving as much information as a single test.[/quote]

I don't know how much it costs, but a short echo costs probably as much as 2* tests if not less at my practice, and will give you much more info, and while it may not be 'convenient' that's not why I run a test. Shouldn't we weigh up the benefits of the test to the patient and the future plan for monitoring and management rather than convenience to us?

As for Dogs- actually NT proBNP is correlating very well with:

Increasing disease severity (Chetboul, 2009,http://onlinelibrary.wiley.com/doi/10.1111/j.1939-1676.2009.0347.x/abstract?deniedAccessCustomisedMessage=&userIsAuthenticated=false)

Rrisk of onset of CHF (Reynolds et al, 2012, http://www.sciencedirect.com/science/article/pii/S1760273412000185 -pretty cool innit!) and

Survival (Serreset al 2009 http://www.sciencedirect.com/science/article/pii/S1760273409000563) in a few recent studies.

I hope similar studies come out in cats, which will help to stratify them better, but especially wishing for a snap/bedside test we can run inhouse. But it still won't stop me having a look at the heart in realtime, in all its technicolor glory...

Best wishes

Raj

Re: Neo mercazole

Martin Atkinson — Mon, 18 Jun 2012 09:39:27 GMT

[quote user="Rajat"]I don't think this is correct Martin. NT pro BNP can distinguish between cats with cardiac and non cardiac cases of dyspnoea, and maybe elevated in cats with severe hypertrophy, but that's it. It cannot tell you 'if the cat needs a scan'. It can pick up severe HCM, or dyspnoea due to heart failure. Several studies show this. Hypertension along with renal disease can also influence NT pro BNP readings. And when NT pro BNP is evaluated as being adequate, it is compared to the gold standard...which is an echocardiogram.[/quote] I suspect you're getting your lines crossed with the usefulness of NTproBNP in dogs and cats. It is presently of less use in dogs and is mainly promoted as a test to differentiate cardiac and non-cardiac causes of coughing but in cats its interpretation is a lot more subtle. In a sample of nearly 50 cats I have now found with one exception that the results tied in with the findings from other methods of determining cardiac failure, including echo, and the levels mirrored almost exactly the extent of cardiac failure. Perhaps the fact that I don't have echo may influence my reliance on this test and the fact that those who do prefer to dismiss it may be of significance! Some work has indeed shown that hypertension due to renal disease influences the results of NTproBNP but IME it did not influence the differentiation between cats with renal disease and those with cardiac disease, and those cats with significantly raised values which had renal disease also had cardiac failure determined by other methods. You're right it 'can't tell if the cat needs a scan', but it can tell you if the cat has significant cardiac disease which would then benefit from additional investigations of which a scan could be one. It is a lot cheaper, more convenient and easier to repeat serially with increasing values giving as much information as a single test.

Re: Neo mercazole

Rajat — Fri, 15 Jun 2012 22:00:43 GMT

[quote user="Martin Atkinson"]

[quote user="Sarah Keir"]For the case in question I would do a heart scan - but then I like scanning everything [/quote] NTproBNP would give enough information to determine whether there is a need for a scan and costs a lot less! It may be raised slightly due to renal disease but IME not enough to effect the diagnosis of heart disease.

[/quote]

I don't think this is correct Martin. NT pro BNP can distinguish between cats with cardiac and non cardiac cases of dyspnoea, and maybe elevated in cats with severe hypertrophy, but that's it. It cannot tell you 'if the cat needs a scan'. It can pick up severe HCM, or dyspnoea due to heart failure. Several studies show this. Hypertension along with renal disease can also influence NT pro BNP readings. And when NT pro BNP is evaluated as being adequate, it is compared to the gold standard...which is an echocardiogram.

While useful in select certain circumstances, I find an echo gives you far more information, and is worth the extra money. IDEXX may market the NT pro bnp test as an amazing tool, one of the VCS meetings I attended there was a talk about it, and the speaker mentioned how he rarely used it, and you'd have been surprised at the murmurs of assent in the audience.

For me, every cat with a murmur should have a echocardiogram.

Best

Raj

Re: Neo mercazole

Mark Hedberg — Fri, 15 Jun 2012 21:36:25 GMT

[quote user="Sarah Keir"]

Anyone had experience of Hills Y/D yet?

Sarah

[/quote]

I went to the symposium and came away a little confused; I understood the point of iodine restriction; but based on some of their points, shouldn't we therefore be reviewing the iodine content of pet foods in general, then? (I cheerfully admit I am not a nutrition expert, I am basing my comment solely on the information gleaned from their lectures.)

Re: Neo mercazole

Martin Atkinson — Fri, 15 Jun 2012 17:25:05 GMT

Re: Neo mercazole

Sarah Keir — Fri, 15 Jun 2012 16:36:15 GMT

Anyone had experience of Hills Y/D yet? I started one cat on it last week so still in diet change stage but after long discussion with the owner it was this or nothing/euthanasia. You can't use it if there is renal insufficiency/CRF so not suitable for the case in questions. Thereotically shouldn't use it in a multi-cat household but from what Hills said at their lunch talk a few weeks ago, they have been feeding it to normal cats for years (10 plus) without any problems/hypothyroidism.

For the case in question I would do a heart scan - but then I like scanning everything

Sarah

Re: Neo mercazole

patrick murphy — Fri, 15 Jun 2012 14:14:43 GMT

I had one that developed an acute pancreatitis when put on them.

Re: Neo mercazole

Stephen Courtney — Thu, 14 Jun 2012 17:40:25 GMT

I find vidalta a real hassle to use in many cases - i think if the cats bite the pill , then they absorb the whole thing at once and a re much more likely to vomit.

I find felimazole the easiest to use by far as the dose increments are so much easier to alter. i am pretty sure a LOT of clients crush the pills and this seems to work well enough for felimazole ( and neomerc) but vidalta there are issues ( not withstanding H&S issues re crushing, personally i think if that's the only way and due care is taken, there is little harm in crushing them up )

I have seen vomiting, diarrhoea and inappetance as the most common adverse reactions to any of these treatments. more rarely, itching especially facial, with terrible and very acute excoriation of the temporal areas. and i have had a couple of bone marrow suppressions, which fortunately resolved quickly on removal of treatment. i had one cat that would only eat on thyroid meds if given periactin ( for no reason at all that we could find, fortunately he died at a ripe old age of 20 before pericatin went off the shelves!)

I find persuading clients to go for radioactive iodine very difficult, even if insured. The prolonged isolation required puts almost everyone off.

And as I get older I am a lot less trusitng, and i think a lot persistent hyperthyroids are down to clients fibbing about their success rate.

The originalk posters cat would appear to have some renal issues, and as the TT4 isn't that high, I'd be disinclined to increase thyroid meds just now. Have you checked blood pressure? Sometimes managing blood pressure and tachycardia can improve things indirectly, by reducing the long term adverse consequences or persistent hyper T4

Re: Neo mercazole

Utlendigur — Thu, 14 Jun 2012 14:53:24 GMT

We've seen at least 2 cats that were started on vidalta but where it didn't seem to fully control the T4 levels and symptoms, even after several dose increases. Client compliance seemed good (weren't crushing or splitting pills, not hiding them in food etc). When switched to felimazole (5mg bid in the one I was dealing with) they stabilised very quickly. I also had a case where I was struggling to stabilise the cat medically, cat was difficult to tablet so assumed due to that, did bilateral thyroidectomy and T4 stayed high, then got rapidly higher. Cat was pts in the end, but a chest xray showed numerous miliary lesions throughout the lung fields so I'm guessing it was possibly a high grade thyroid neoplasia?

Re: Neo mercazole

Martin Atkinson — Thu, 14 Jun 2012 14:26:36 GMT

You have to primarily doubt client compliance in this situation and decide if you trust the previous vet's surgical skills given his/her previous management of the case. Feel for goitres but even if the thyroids have been removed correctly, it is not uncommon for adventitious thyroid tissue to be present in the thorax. Scinitigraphy would reveal this and radio-iodine treatment is an option or medication may need to be continued. I've seen it all in my time - I had one cat that had bilateral goitres which I recommended should have radio-iodine therapy, client declined on cost and chose medication (only with neo-mercazole in those days), then went for bilateral thyroidectomy as he was impossible to pill, despite my best surgical skills he had persistent hypo-calcaemia which was even more difficult to monitor and treat, hyperthyroidism recurred, scintigraphy revealed thoracic thyroid tissue, had radio-iodine therapy several years following initial recommendation, hyperthyroidism resolved but he went to his grave being treated for hypo-calcaemia. Lets hope yours doesn't turn that complicated but it depends on the will of the client now I'd say.

Re: Neo mercazole

CatherineThomas — Thu, 14 Jun 2012 13:51:42 GMT

[quote user="Mark Hedberg"]

He's had a bilateral thyroidectomy and the numbers are still high? Color me impressed...

[/quote]

I know, when the owners said that he had his thyroid removed and it had failed I assumed they meant only 1 had been removed, until I read the notes properly.

Re: Neo mercazole

Martin Atkinson — Thu, 14 Jun 2012 13:49:09 GMT

[quote user="Mark Holmes"]

[quote user="Martin Atkinson"]which is IMO neo-mercazole via the back door [/quote]

Easier then tableting I guess.

[/quote] And Intervet isn't even a French company!

Re: Neo mercazole

Mark Hedberg — Thu, 14 Jun 2012 12:45:37 GMT

He's had a bilateral thyroidectomy and the numbers are still high? Color me impressed...

Re: Neo mercazole

CatherineThomas — Thu, 14 Jun 2012 11:09:42 GMT

Well I've just had a better look through his history and it seems that he was first diagnosed Aug 2010. He was started on vidalta, at his first re-check the t4 was still high so for some reason he was changed onto felimazole. then he had miliary dermatitis. Fleas were also seen. The flea problem was treated but the miliary dermatitis continued, despite depo-medrone injections. The notes seem to say that they thought the dermatitis was due So he had a bilateral thyroidectomy. A month after the thyroidectomy his T4 was checked and found to be still high. So he was started on neo-mercazole, this was Jan 2011. He's been on 1 tablet bid since then. it doesn't look like he's had a blood test since then but in May 2011 he was reported to be polydipsic so a urine sample was analysed - SG 1.015, pro trace, leu ++, rest negative, pH 7. In jan 2012 he was found to have a heart murmur and HR 180, weight 5.04kg. Bloods were declined.

On tuesday I saw him for the first time. He weighed 4.65kg and had a grade 3 heart murmur and HR 200. Blood results show T4 65.6 (13-50), urea 13.8 (5-10), Creatinine 162 (40-150). I plan to get a urine sample from him.

Re: Neo mercazole

Mark Holmes — Thu, 14 Jun 2012 10:55:02 GMT

[quote user="Martin Atkinson"]which is IMO neo-mercazole via the back door [/quote]

Easier then tableting I guess.

Re: Neo mercazole

Martin Atkinson — Thu, 14 Jun 2012 10:45:32 GMT

[quote user="Stephen Courtney"].... i have one cat on neomerc because everything else made her vomit or caused skin eruptions. Why neomerc is fine, i have no idea. but because of the cascade it is your last option. S[/quote] Strange isn't it that I found these symptoms occurred with neo-merc but never with Felimazole so I couldn't see the point of using Vidalta which is IMO neo-mercazole via the back door of the cascade!

Re: Neo mercazole

Stephen Courtney — Thu, 14 Jun 2012 10:29:24 GMT

What Wynn said - you can go a lot higher if you have to but if the cat is otherwise well, normal heart rate, kidneys working OK, and you have checked urine SG I'd watch for a while.I prefer to get my hyperthyroids in the lower half to third of the normal range, and so long as they are doing clinically well there, I am pretty happy

Next dose rate up would be 5mg tid, i never had many go over this , currently i have one cat on neomerc because everything else made her vomit or caused skin eruptions. Why neomerc is fine, i have no idea. but because of the cascade it is your last option. So long as you have evidence in the history that licensed meds have been tried, problems arose, and owner has given informed consent, your rear end is nicely covered.

Re: Neo mercazole

Lorna McHardy — Thu, 14 Jun 2012 10:25:49 GMT

When you say "a little high"... how high, and is the cat stable or deteriorating clinically? Unless it's very high rather than just slightly over the reference range for normal, I'd go by the clinical symptoms and if they're ok, leave the dose alone for now.

Re: Neo mercazole

Martin Atkinson — Thu, 14 Jun 2012 10:24:28 GMT

I would question the 'Felimzole/Vidalta didn't work' statement. Given Vidalta is the same as neo-mercazole and IME thiamazole works better this is strange, sounds like someone before you didn't work through this case very well or there is a lack of client compliance. You say his T4 is a little high but what are the figures, and what other symptoms are there presently?

Re: Neo mercazole

Bob Russell — Thu, 14 Jun 2012 09:32:45 GMT

We have one cat on 25mg bd! Otherwise well but this one has been trouble getting to settle for some time. I have discussed surgery and radioactive iodine but the cat is elderly and the owners are unwilling to do anything different.

Re: Neo mercazole

Hannah Wynne Richards — Thu, 14 Jun 2012 09:29:06 GMT

What are his liver/kidney parameters ? You've got to treat the patient-not the T4

Wynne