Liz Bode
Forum Replies Created
-
AuthorPosts
-
Hi!
Lovely to hear from you so far. I really hope that you find this course useful. My plan post-Covid (if there is such a thing!)is to also do some echo courses with a couple of echo practical days. I’m always looking for feedback or suggestions of future topics so please feel free to post here too.
Liz
Hi Nathalie,
This is a good question! I think it comes down to the fact that if there was a murmur due to a VSD it is most likely going to be louder than that associated with relative pulmonic stenosis. As a VSD murmur and PS murmur both occur in systole you wouldn’t be able to hear the relative PS one, only the VSD. Relative PS will be very quiet. You hear a relative PS murmur associated with an ASD because there is no murmur from the ASD itself, the pressure in the atria is too low to cause one. Generally, you can only hear a murmur when velocity of blood flow is >2m/s.
Hope that makes sense!
Liz
Unfortunately, that is something we have to accept. It happens to me all the time too! If stroking the nasal planum does not help, and gabapentin doesn’t either then that is all you can do 🙂
Hi Nathalie,
Yes, that is correct. As the heart ages is gets stiffer and less compliant so you can here a gallop sound due to diastolic dysfunction in this group of cats, and this wouldn’t be pathological. Cats with a cardiomyopathy have stiffer ventricles (and so diastolic dysfunction) but this is pathological.
I don’t know if you perform Doppler echocardiography, but we can appreciate this on echo when we look at relaxation patterns. Cats with HCM and older cats (from around 10yrs) will have grade 1 diastolic dysfunction or an impaired relaxation pattern on E and A waves across the mitral valve. This is the stage of diastolic dysfunction BEFORE left atrial pressure rises.
Therefore, if we hear a gallop sound in an older cat we cannot know, without echo, if this is associated with a normal, aged heart or a heart with a cardiomyopathy.Hope that helps a bit.
Liz
Here is a link to the notes for this lesson too;
Any problems let me know.
Liz
Hi Areti,
In cats with CHF of any cause I would now use furosemide and clopidogrel only. Possibly spironolactone too as we haven’t any good evidence for or against this currently. There was a recent paper by King et al (2019) that showed no benefit of ACE inhibitors either in CHF or pre-clinically.
In pre-clinical HCM I don’t use anything. In severe HOCM I do use atenolol still.
Hope you have a lovely weekend,
Liz
That all sounds good. If they’re normal then it’s likely to be the case and I wouldn’t be too concerned. Fractional shortening is a poor marker of systolic function as it’s affected by so many variables so I’d rely more on chamber dimensions in this case and if the owner wants to pursue it I’d look at other markers of systolic function.
I have in my head (anecdotally) that I get a few advice requests with Labs and cardiac silhouette queries and they generally turn out to be normal. Occasionally we see tricuspid valve dysplasia/ mitral valve dysplasia or degeneration and sometimes DCM but relatively rare for the latter compared to other breeds. Always good to check it out though.
Liz
Hi Emma,
Good question!
It really depends on your premed, induction and inhalational agents. There are many publications on the effects of various sedative agents on heart function. Generally, things like opioids do very little, even ACP and alfaxalone. Obviously, any alpha2 can, especially on systolic function.
Generally, I think that GA does not overly affect heart size but it will have the potential to alter systolic (and perhaps diastolic) function. Therefore, if chamber sizes are normal then they are normal, but you cannot tell anything about systolic function from your echo.
If the dog had increased chamber size then this may be real. However, I would always want to repeat an echo without sedatives/ GA if any abnormalities were present, where possible.
Hope that helps a little.
Liz
Hi Areti,
I can help with your NT-proBNP question 🙂
An abnormal result of >270pmol/l in a cat with signs of dyspnoea (this is an abnormal result on a SNAP test) is highly specific for CHF. The SNAP test will also pick up an abnormal result if levels are 150-270 and again in a cat with clinical signs of CHF this is specific.
A SNAP test should be followed up by a quantitative test where possible.
As a screen for heart disease NT-proBNP is less effective in cats without clinical signs. Specificity and sensitivity are between 80-95% depending on the cut-off used. If you get a high result – >150 in a cat with a murmur (although as you know cats with HCM don’t always have murmurs) a gallop or arrhythmia then the cat probably has heart disease. Although a cat with an arrhythmia almost certainly has heart disease anyway! A result of 50-100pmol/l probably means that it doesn’t have HCM BUT cats with heart disease do occasionally have low results.
If you can perform echo, even just a basic echo, this is superior to NT-proBNP but I’m aware that this isn’t available to everyone.
I wouldn’t advocate using NT-proBNP as a screening tool generally. However, where your suspicion of heart disease is high and owners won’t go for an echo straight away it could be a good tool to use – and if it’s high it might make owners opt for an echo.
Hope that helps!
Liz
Hi Emma,
Some great questions. The best place to look for a protocol when treating dogs and cats with heart worm is the American Heartworm Society – they have very detailed guides, regularly updated and a ‘how to’ protocol. I have also written a webinar which you should have access to 🙂
https://www.heartwormsociety.org
A positive Elisa should be confirmed with additional tests as false positive are found and melarsomine is not a nice drug!
Treatment really depends on the severity (how symptomatic the dog is) of heart worm. Dogs that are symptomatic should get steroids, doxy, macrocyclic lactones and melarsomine (you can get it in UK but needs to be imported). Thromboembolic disease is usually caused by the worms themselves so possibly why clopidogrel/ aspirin aren’t advised.
Hope that is helpful.
Liz
Hi all,
I, obviously, love a heart worm case – although I have only ever seen one case of it in the UK. I have had advice calls about them and seen some cases when I was doing an externship in US. The case I saw was also a rescue from Romania and presented to me OOH as a resident in Edinburgh (where you’d least expect heart worm to be) with 3rd degree AV block. When we imaged it there was endocarditis (unrelated to heart worm, but probably myocarditis as an extension of the endocarditis was the cause of the AV block – the aortic valve is anatomically very close to the AV node). We took bloods and, routinely, did blood smears which a student looked at first for me – they came back to say they could see worms!!! We were so surprised – there were loads of microfilaria squirming around in the dog’s blood! We treated the heart worm, endocarditis and the dog did much better than we thought. The 3rd degree AV block even resolved and so we did not need to place a pacemaker.
Just thought I’d share a case with a more positive outcome ?
Liz
Hi Kerida,
Andy might be able to help with video posting here as I’m not sure. Other option would be to use the clinical advice service and submit them through there. You have advice credits with your membership. If that’s tricky email them to liz@vtx-cpd.com
Let me know if any issues
Liz
Hi Kerida,
Thanks for uploading the history and the radiographs to the discussion forum, what an interesting case!
I think there is evidence of some cardiomegaly, particularly at the base on the laterals. You can’t really see the right atrium on these as it is buried in the middle of the cardiac silhouette (unless v severe tricuspid dysplasia, which cats do not often get and this is the wrong age). It is hard to confirm specific chamber enlargement on the DV as the silhouette is effaced by the lung pattern. I see what you mean on the left lateral, there looks like there is some sort of mass cranio-dorsal to the heart. I can’t see this on the Dv, but the slight rotation makes it hard to look at the right-cranial thorax. The heart is rounder on the left lateral, but I think we tend to see this so can’t read too much into that.
The lung pattern is diffuse broncho-interstitial with a greater interstitial component in the caudo-dorsal lung fields.
You don’t mention any murmur/ arrhythmia/ gallop so I assume that these are not present?My DDx would be:
Oedema – cardiogenic vs non-cardiogenic superimposed on feline asthma type pathology
Infection – bronchopneumonia
Possible mass in cranial thoraxIs there any way this cat could have a FAST scan of the thorax to rule in/out cardiomegaly and a mass? I think that would be the single most useful test here?
What did you decide to do with the cat in the end? Interesting that the brother died of resp issues too…
I would be very interested to see what others thought 🙂
Liz
Hi Scott,
The medics are behind the curve 😉 Cardiologist’s have been using gabapentin in cats for ages pre-echo. It works for some and not for others (although always worth a try) and we tend to use a dose of 50-100mg/cat 1-2 hours pre-appointment. I think we also need to be careful in cats with renal disease as it is exclusively. excreted via the kidneys. I thought there had been an abstract on echo parameters and gabapentin, but I can’t find one. There has, however, been one on trazadone and they found that it worked in some cases and avoided the need for other sedatives. However, it did significantly lower BP (although BP was taken in cats prior to use so it makes sense that BP would be lower after trazadone if they are less stressed!). I’ve never used trazadone in cats though.
Liz 🙂No problem 🙂 That sounds like a cool case. I always think comparing what you find to the human literature is super interesting, so you would want to do that. If there are any case reports/ case series of similar things in the veterinary literature you would want to compare your case to those too (if there aren’t you might consider writing this up!). If there was anything unusual about this case or things you didn’t do due to financial limitations then talk about this in the discussion too.
Hope that helps.
Liz
-
AuthorPosts