Small Animal Cardiology

What are the most crucial history questions?

Why is it important to find out whether the cough is productive or not?

How could we find out if the cough is productive or not if the owner has never noticed anything 'coughed up'?

Poor Mr Darcy has a cough which occurs when pulling on the lead or after drinking, but can be spontaneous too. Also, no swallowing…

It's really important to differentiate seizure from syncope. What history findings would suggest seizure?

Yes, facial twitching, jaw champing, salivation, vocalisation and limb paddling all point towards a neurological problem.

Mr Darcy has a non-productive cough with a single episode of syncope (no neuro signs but was unconscious). Here we have a definite association with a cough; otherwise the non-diagnostic rate in single episode syncope is very high.

So shall we work up the syncope or the cough first?

On physical exam Mr Darcy has a heart rate of 88bpm with a left sided murmur (PMI left apex) and phasic irregularity (regularly irregular rhythm). Respiratory rate was 44bpm with increased lung noise, possibly crackles.

So what can we hear on auscultation?

What's the difference between a grade 3 murmur and a grade 4 murmur?

Our key findings were a medium grade systolic murmur with a regularly irregular rhythm.

What are our DDx for the murmur?

So we've got mitral valve insufficiency as one of our DDx. This can cause congestive heart failure – how does this lead to coughing?

And how does it cause respiratory signs?

Mr Darcy's respiratory pattern has an expiratory effort and on examination of the abdomen it's easy to feel external abdominal muscles.


What are our top 3 differential diagnoses for the respiratory signs?

Quick poll – do we think congestive heart failure is likely or unlikely in this case?

So CHF is unlikely…What shall we do as our first diagnostic test?

Here we go!

What abnormalities are visible on the radiographs?

Although we think Mr Darcy's heart looks big, it's hard to assess cardiomegaly in smaller terrier breeds like this – their heart always 'looks big' on radiography. How else can we assess it?

Let's look at an echo of Mr Darcy's heart – if the left atrium is a normal size then we can pretty much rule out congestive heart failure from our list of DDx.

What disease is present? Is Mr Darcy likely to be in congestive heart failure today?

Are there any other indicators that Mr Darcy is not in CHF other than his normal left atrium?

OK, so Mr Darcy has heart disease but it is NOT responsible for his cough, tachypnoea and increased respiratory effort.

Let's come up with 2 differentials for the respiratory signs.

So what shall we choose as our next test? We need to know how important the lower respiratory disease is (if it is there at all)…

So Mr Darcy has degenerative mitral valve disease but no left atrial dilation. He has mild lower airway inflammation but nothing shocking…What does this leave us with?

Any more diagnostics?

We're nearly done! It's a common presentation to have mitral valve disease and respiratory disease; would we give anything to treat the cardiac disease?

Anything else we could do?

So how is Mr Darcy getting on?

Thanks for such a brilliant #VetFinals Kieran!