What the hell is HHT?

What is HHT?

Most readers will come to this post from AFib forums and FB pages methinks.  And so, the title “HHT and AFib athlete” will be a bit mysterious to them.

HHT is a common rare disease!  Yes, I know that is an oxymoron.  One person in 50,000 is diagnosed with it but campaigners believe 10 times that number may have it (i.e., 1:5,000).  So, in Britain that would mean about 1340 diagnosed cases but 13,400 undiagnosed!

Here’s one scientific explanation of the condition from the Internet:

 

Hereditary Haemorrhagic Telangiectasia

HHT is a hereditary, autosomal dominant disease of the blood vessels, which means that children of HHT patients have a 50% chance of inheriting the disease.

Hereditary Haemorrhagic Telangiectasia (HHT or Rendu Osler Weber disease) is a relatively rare disease, and as a consequence, doctors often have little experience or knowledge of the disease. It is a complex disorder involving both a genetic susceptibility and other internal and external (environmental) factors.

The characteristic abnormality of the blood vessels is a dilation at the site of the capillaries. Normally, arteries divide many times into smaller arteries and end in the capillaries. These capillaries fuse again to form the veins. In HHT, we find dilations instead of capillaries at certain spots.

These abnormalities can occur anywhere in the body, since all the blood vessels are subject to the same hereditary deficiency. However, there are predilection sites, such as the skin on the face and fingers, and the mucous membranes of the nose, mouth and digestive tract. Usually, these involve small dilations of several millimetres, the so-called telangiectases. These bleed easily – e.g. as nose bleeds – because of their thin walls and superficial position. Other predilection sites are the lung, brain and liver. These usually involve larger abnormalities (up to 10 centimetres), the so-called arteriovenous malformations (AVMs). The AVMs tend to bleed less because they are protected by surrounding tissues. However, other symptoms may be present depending on which organ is affected.

 

 

Or in plain English, we have missing capillary beds or “curly veins”.  This means there is too much pressure being returned to the veins.  The most obvious symptom of this is nosebleeds, which 90% of HHTers will have.  These can be horrendous.  My case is perhaps medium mild, but I have had to have the veins in my nose ablated by laser three times (under general anaesthetic) and also a skin graft from my thigh put over the bleeding area (inside the nose) to stop the bleeds – all these only work for a while as, being a genetic disorder, the troublesome artery/veins will ‘regrow’.

My worse nosebleed was 300 mls and about 50 minutes.  At its worse these were happening several times per week. Enough to make you feel truly dreadful afterwards.  Some people will have bleeds that last for hours and require blood transfusions every few weeks.  Obviously, all this can lead to anaemia (low iron in the blood) and thus impaired oxygen uptake.  This may be the mechanism by which HHTers get AFib.

I have malformations in my liver and, in rare cases, this can mean that the pressure being returned to the right side of the heart is too high and can lead, over the years, to right sided enlargement and heart failure.  Ultimately, there is no cure unless you are lucky enough to get a liver transplant – if lucky is the right expression in this case.  

This right sided enlargement may be what has triggered my AFib, although the Electrocardiologists always treat the left side.  To be frank, the research on HHT is severely lacking. 

You can also have malformations in the lungs, digestive tract and brain.  I was really chuffed after ablation number two when having gone to hospital with what turned out to be a kaleidoscope migraine, I had an MRI scan of the brain and it revealed no hidden nasties in my brain.  Good news indeed as these can kill you.

The main effect for me as a HHT athlete is inconvenient nosebleeds which can make you look like you have had a run in with a chainsaw massacre during your run.  Oddly enough this has only ever happened to me a few times.  Bleeds, for me, are most likely in the morning when the nasal passages have dried out. 

Upside down or curled up postures such as Down Dog or Child’s Pose in Yoga can be problematic as these increase the pressure in the nose, but I tend to do them anyway.

Large quantities of vegetables, as in a smoothie, thin the blood too much and cause more bleeds as does fish oil capsules or too much alcohol, especially, in my case, red wine.  But being as I seem to be permanently recovering from either a cardiac ablation or a cardioversion at the moment, I’m avoiding alcohol completely.

And obviously, being on anti-coagulants for the AFib is a nightmare although the perfect timing of having a skin graft up my nose just before my AFib journey got problematic was useful – even if the dehydration caused by eight hours without water (why do they do that!) did trigger AFib episode number 3.

Talking of being an ‘athlete’ there are few famous people known of with this disorder.  The most prominent is authoress Catherine Cookson who donated huge amounts of money to research into this disorder.  I  have heard rumours of a top British sportsperson with HHT, but nothing has been released publicly – which is a shame as it would be nice to have some role models.

And now you know more than most hospital Ear, Nose and Throat Specialists – and that is NOT a joke!  I’ve had many ENT doctors be unaware of a condition which manifests itself mainly as nosebleeds.  Usually, I am the one guiding them!

 

www.med.unc.edu

https://www.antoniusziekenhuis.nl/hereditary-haemorrhagic-telangiectasia