Fainting horses - vaso-vagal syncope, any ideas?

[Nudibranch]

On Monday night my 13 yo tb mare collapsed twice, once when pulling the leg forward to stretch under the girth and again almost as soon as we moved off to ride. (I thought the first one might have been me unbalancing her, but seemingly not!)

Vet came out last night, everything seems normal, I suspected it might be a back thing but he reckons hers is fine. Thought he didn't actually check until I mentioned it, and then only very briefly. His first and current guess is vaso-vagal syncope, which is basically just fainting. Her heart is normal, or at least it is at present... from what he has said it seems the diagnosis is very difficult, since 99% of the time there's nothing wrong! He's taken blood, etc and we will start testing to rule out any other illness. Has anyone else had any experience of this?

Vet seems to think the ECG and various tests won't show anything, therefore it's going to be a black and white case of - do I ride her or not? I know she will be fine most of the time but as she is now a hack, and if it happened on the road, well, it could be fatal for one of us. On Monday night it was pure luck I wasn't crushed underneath her as she went from totally normal to flat on the floor in a split second.

Am I being melodramatic thinking this is the end of her working life, or is it sensible? Help!

 

[aimeerose]

I think you are very sensible to want to get to the bottem of this, and i certainly wouldnt ride in the meantime, far to dangerous for both of you

I would get her very carefully checked out by a specialist horse vet as your vet seems to be vague and not giving you the much needed answers, it could be a number of different things, and the prognosis will depend on the condition.

i would also check back/tack etc

 

[Nudibranch]

I agree, though the vet is a specialist horse vet! She only wears a french link snaffle, teeth were fine when he checked. She was also wearing a treeless saddle at the time...theoretically this should be a positive thing though I'm starting to wonder. She normally wears her High Wither without any problems other than the fact she's a highly strung half mad ex racer!
It's a tricky one....

 

[AndyPandy]

Vaso vagal syncope can be diagnosed with a Holter monitor (a portable ECG), which can record the cardiac activity constantly and can be linked up with the fainting. VVS can get worse and cause severe problems (in fact it killed our puppy that had it earlier this year).

If you can afford to, get the horse referred to a cardiac specialist. There are some good ones around.

 

[alleycat]

My TB mare used to do something like this, always when being saddled; stretching her foreleg to remove under-girth wrinkles was an absolute invitation for her to go down. She would collapse onto the concrete yard and lie as if senseless; it was pretty spectacular and distressing; the first couple of times we loosened girths and made sure she wasn't choking on her tongue and still she lay there. I discovered in my desperation that if you dropped a metal bucket behind her she would wake up and get to her feet, looking slightly insulted; but otherwise as if nothing had happened. She would be fine to ride after that! She never did it when actually being ridden.

We never did get to the bottom of it, but came to accept it as an extreme form of being "cold-backed"; she never hurt herself or anyone else and despite the drama of the collapse and the impression she gave of having fainted, I have a feeling that she wasn't totally out of control of what was happening; although she wasn't actually putting it on, either.

She didn't seem to have any specific back pain that could explain this, but with hindsight I am sure that the saddle and girth were behind it; she would go down not just when girthed up but in EXPECTATION of being girthed up, when the girth was still hanging in swathes. The act of going down would then tighten the girth.

I tried everything I could think of, including taking her girth and saddle-cloth down to the stable wrapped round a hot water bottle on cold days.

I found the girth made a difference; a supple leather balding girth seemed to help her; elasticated girths were the worst.

However the one thing to make a real difference was to let her walk round and round the box whilst being saddled; highly impractical but totally successful as far as the fainting went. I then led her out with her girths still loose and tightened them walking round the yard. Obviously I looked an utter idiot, because several faint-free years later, when I lent the mare to a far more experienced rider than myself, with a reminder to "let Alley walk around while you saddle her" the experienced rider decided she wasn't going to be such a prat; tied her up; girthed her up - and DOWN she went!

I think in hindsight I should have taken this more seriously instead of just acepting it as one of Alley's little quirks; although we could not find any back problems at the time, in later life her back did give her gyp; always cured by rest; and I suspect her biggest back problem was actually ME sitting on her (professionally fitted) saddle. I eventally put a cheap synthetic saddle on her and she was like a different horse.

I think that you are right and that your TB is trying to tell you something about the treeless saddle. Hope this helps.

Edited to say that "theoretically better" didn't work for Alley either; this was the horse that was so freaked out by a change from a joited to a mild straight-bar snaffle that she bolted, and didn't stop until I had the sense to drop the contact.

 

[foolsgold]

my mates dales pony was diagnosed with VVS, he had collapsed onto our EDT (ouch! luckily unhurt) a year before and worsened from there. It got to the point where he fainted in the field just from lifting his head suddenly. He saw 2 vets who kept saying he's fine, horses can't faint! Luckily 3rd vet took it seriously. His heart was normal but bloods came back as anaemic and low in copper. He had a course of haemavite-B and has been on coppertrition ever since. Interestingly, the one time he fainted since has been when mate missed a dose of coppertrition. As for riding him, vet says only you can decide. Mate decided he's worth the risk, but only she and i ride him, as we can recognise the early warnings. Have since been told lunging or trotting in hand before you ride decreases the risk of a faint,or anything that raises heart rate, and you could also speak to a nutritionist, NAF were helpful with us, they recommended a salt lick, electrolytes in hot weather and optimum feeding rate of a quality vit/min supplement amongst other things. We also kept a diary of his attacks, what he was doing, how long it lasted, weather etc. to help recognise warning signs. Hope this helps