heart attacks in horses

[Sol_Gemma]

are these common? my boy is 25 this year and i worry about him
we do 3-4 30 minute hacks in walk a week, plus a 30 minute lesson which he enjoys as he's a dressage schoolmaster. Im trying to keep him reasonably fit, but keep everything gentle. I just want him to be comfy and happy but today on the way to the yard i was thinking what if he's had a heart attack in the night or something :eek:

[domane]

Well unfortunately, none of us knows when our number is going to be up so try not to dwell on it. You wouldn't be human if the thought (worry) didn't cross your mind occasionally. Sounds like your boy gets some nice gentle exercise and if horses are like humans, far better to be doing something than nothing! There are loads of horses on here in their late 20's who pelt around like they are still 5 - I'm sure you will get loads of people telling you too, in due course!!! :)

Try not to worry and ENJOY your horse!!!

[Bay Mare]

It's natural to worry as our animals get older (I often poke my poor kitty if he's too quiet) but all we can do is love and enjoy them while they're with us and make sure that they have happy and healthy lives.

[becs]

We all worry as they get older - mine are 21 and 32 years old, so I know how you feel.

But don't forget the risk of heart attack is quite different to horses than humans and it occurs a lot less. They don't over indulge in artery-blocking food every day like we do, with their herbivore diet. A vet once said the hard thing with horses is that most of them deteriorate slowly as they age, so we have to make the tough decision for them.

Sound as though you have a good regime going there, with regular light work for him to enjoy. It's the routines they seem to like. Keep it up and enjoy him every day.

[Sol_Gemma]

They don't over indulge in artery-blocking food every day like we do, with their herbivore diet. A vet once said the hard thing with horses is that most of them deteriorate slowly as they age, so we have to make the tough decision for them


i didnt think about that, good point :D i know his time will come one day :( but i think it *might* be a little easier for me if i have to call his owner and we maybe have to pts rather than a nasty shock. Hopefully not for years yet, he's in good health. Thanks everyone i feel better now

[magicalmac]

Try not to worry to much although its only natural to. My boy is 28 he hacks 2/3hrs 4 times a week including canters, trotting, hills and the occassional jump [over logs etc]. He only retired from the hunting field last year [a notorious place for heart attacks]. I do make sure the vet gives him a full MOT every 6 months but at the moment he is still giving the average 5yr old a good run for their money.

[parsharainbow]

what panicks me is not the fact that my boy might have a heart attack (I'd rather he went quickly than suffered slowly although either would be awful and devastating) what would happen if he had one when I was riding :o that really scares me :o

[ClaireBear_nz]

This won't help at all! My sisters horse was in good health, and was only 17, when the vet thinks he had a mild heart attack, ran through a fence, got caught in the second, where he struggled and his aorta burst. We found him dead in the fence in the morning.

However, I have a pony whos aged between 25 and 30, and who was eventing to 3ft until mild arthritis in her knees forced her to stop!

[marsden]

i won't worry! My boy sounds quite like magicalmac horse. He is also 28 and goes out about 4 times a week, it will be increasing to 6 once i'm finished uni and he's back in full fitness. Hes out 24/7 galloping about and playing with the youngsters (which to be honest isn't fun to watch), he goes out hacking just like any other young horse. Don't worry about it and just enjoy the time you h ave with him :D

[becs]

Firstly heart attacks (as in myocardial infarction = death of part of heart muscle due to insufficient oxygen to it, usually from blockage) in horses are rare. Horses may drop dead and vets may suggest that as a possibility, but, without a PM, in most cases we never know. They may have had a massive stroke, clot to the lungs, ruptured aorta etc - but without expensive explorations, there are rarely clear clues. Hence stats of causes of death are not as accurate as humans - not as many are done per death.

Even if they had a true heart attack, they're not always fatal - if the heart muscle area affected is small enough, they may be very ill but not always die.

As for what if they had one when ridden, they may well slow down and become breathless / difficulty breathing due to pain, dropping their head and becoming weak, before collapsing. Eg you may well get a clue that something is VERY wrong and it's time to dismount immediately. They won't always keel over sideways in 2 seconds IMHO.

Overall I think we're far more likely to be walloped by a car on the roads when hacking - there are many other greater risks to think about minimising. And if they did die suddenly, remember the loss is ours - they didn't suffer a slow miserable decline like many horses do.

Remember - "dream like they'll live forever, live like they'll die today" (tweaked for horses, lol). Eg enjoy them and, if you're doing all the right things, as you are, try not to worry (she says to herself).

[parsharainbow]

As for what if they had one when ridden, they may well slow down and become breathless / difficulty breathing due to pain, dropping their head and becoming weak, before collapsing. Eg you may well get a clue that something is VERY wrong and it's time to dismount immediately. They won't always keel over sideways in 2 seconds IMHO.

.

Thanks for that :) I feel a lot better for having read that :)

Sorry for hijacking the thread :o

[becs]

Found some fascinating facts doing research on this thread...

per BHS Vet Manual

re. blood vessel disease (cause of MI),
...the atheromatous cholesterol deposits of man are very rare in equines.

re.thrombosis (blockage of blood vessel)
the thickening etc of the aorta wall with age that precedes these events may be due to repeated strongyle (redworm) larvae trauma.

These "larval implications" are mentioned re rupturing aneurysms too.

Looks like worming was even more important than I realised!

[Sammii]

The chances of a heart attack happening in an older horse are no different (roughly) to the chance of a heart attack happening in a younger horse.

July last year, we lost one of our liveries (both horse & rider) due to the horse (8yo WB) having a heart attack whilst out hacking. There are many things that can cause a heart attack....and none to prevent it happening.

The way I think about it is: If you can't prevent it, don't stress over it. :)

[becs]

I think the important bit to get across in this thread is we can't relate human heart attacks to horsey ones - different incidence rate, causes etc.

[Bay Mare]

I think the important bit to get across in this thread is we can't relate human heart attacks to horsey ones - different incidence rate, causes etc.


Very true! 'Heart Attack' is the incorrect term to use as horses don't tend to get heart attacks (myocardial infarctions).

They can, however, get other heart problems but none of these are, strictly speaking, heart attacks. Heart rhythm problems can be an issue, congenital abnormalities and aortic aneurysms. These could be monitored and picked up if the horses were screened (heart rhythm problems are not so easy unless you are making a recording during the arrhythmia) but cardiac echos would pick up the congenital defects. The horse would need regular echos if you were going to pick up an aneurysm so it's not a definite answer.

Atrial fibrillation (I can explain it later if you're interested) can be an issue as it can cause blood clots to go to the lungs or brain causing pulmonary embolism (blood clots in the lungs) or cva (stroke).


At the end of the day, though, we can't go through life worrying about 'what ifs'. The only certainty is that one day we will all pass over. In the meantime we need to enjoy our lives and cherish those (including our animals) who we love and care for.

[becs]

Echo Bay Mare - she has put it into better words than I could! That's what I was trying to say. Because when humans die suddenly, it often IS a heart attack /MI, we tend to think that way to our dear horses too. They may "drop dead" sometimes but there are many other causes, heart & otherwise. Sadly we often never know why.

Atrial fibrillation (I can explain it later if you're interested) can be an issue as it can cause blood clots to go to the lungs or brain causing pulmonary embolism (blood clots in the lungs) or cva (stroke). coo that's really interesting - AF was regarded as relatively minor in my day; just slap 'em on digoxin and that's it!

[Bay Mare]

The digoxin is used to slow the heart rate down as untreated atrial fibrillation (AF) tends to be associated with a rapid heart rate. Unfortunately this doesn't do anything about the fibrillation.

Because the atria don't contract correctly in AF (if you saw the atria they would look like a wobbling jelly) it means that there is a higher chance of getting blood clots and these going to the head or lungs! In humans we would ALWAYS (unless there was a VERY good reason) give them some form of anti-coagulation (blood thinners) such as warfarin or aspirin. I haven't heard of blood thinners being used in horses though so presumably this isn't so much a problem!

Another issue is that although there isn't always an apparent reason for AF it can sometimes be associated with valve disease.

There is a treatment occasionally use in horses which is a 'cardioversion' where an electric shock is given to the heart which stops the heart in the hope that the heart will restart again in a regular rhythm (this is also used in humans). It can work but if the AF is longstanding there is less of a chance of success.

It's a shame that equine cardiology hasn't evolved as there is a treatment in humans that could probably be transferred over to horses. This is called an 'ablation' and, basically, the focus of some forms of AF can be found around the pulmonary veins. When these have been identified radio frequency is used to 'isolate' these focii so that they can't set up an AF 'circuit'.

Maybe AF isn't such a problem in horses and, to be fair, it tends to show up more as a problem in horses working at higher performance levels.

Sorry ... hope that was slightly clearer than mud :)


This is an ECG of AF:


http://www.tufts.edu/vet/vet_common/images/sports/performance/figure2.jpg

The spikes are the ventricular contractions which you will see are spaced out at irregular intervals, this is a feature of AF! If you look between the spikes you will see that the 'baseline' is all wobbly, this is the 'fibrillation' where focii from all over the atria are firing and behaving erratically.