Postural orthostatic tachycardia syndrome (POTS) and the vagus nerve

From DoctorMyhill
Jump to navigation Jump to search

Date of first publication of this page

This page was first published May 2021.

More ideas on POTS

One of the great joys of Craig and Katie’s private Facebook group is that members are happy to try new treatments on themselves and share the results. Dawn has been one such pioneer and her experience has given us new insights! Dawn is severely afflicted with POTS and has been highly motivated to work out the mechanisms of such.

[Please see My Social Media Presence for full details of my Facebook groups and my other social media platforms.]

What happens in POTS

On standing up-

  • The heart rate speeds up, sometimes by 30 bpm or more.
  • Blood pressure starts to fall, sometimes as low as 90-40

This results in acute symptoms such as faintness which, if ignored, may progress to loss of consciousness.
You have to lie down very quickly for recovery

Why POTS is a particular problem for us vertical humans

Most mammals spend their lives on all fours. This makes for simple blood pressure control – the animal spends most of its time with the heart on the same level as the rest of this body. For my Patterdale terrier Nancy, all the muscles that work her limbs are largely central and close to the heart. This is very different compared with monkeys. AND when our primitive ancestors moved into the trees they had a very particular problem. How to maintain blood pressure when vertical, horizontal and sometimes upside down? What was needed was a mechanism that controlled blood pressure (so when vertical there was arterial constriction in the lower limbs and dilatation in the upper limbs, then vice versa when upside down) together with mechanisms to increase heart rate when vertical or upside down and reduce it when horizontal. And all this has to be done automatically as the brain of Tarzan would surely be on other things – like Jane! A very tricky monkey business!

Film History Aside: “Me Tarzan, you Jane.” is one of those famous 'misquotes'. Johnny Weissmuller never actually said those words in that order in any of the Tarzan films. Nor did that phrase appear in any of the original books or stories as written by Edgar Rice Burroughs.It is said that this misquote arose when Weissmuller was being interviewed for a piece in the June 1932 issue of Photoplay magazine. Weissmuller said - “I didn’t have to act in Tarzan, the Ape Man — I just said, ‘Me Tarzan, you Jane.’” 

So the autonomic nervous system evolved with the sympathetic nerves firing off signals as we went vertical (more powerful heart beat, perhaps faster heart rate and blood vessel constriction) and the parasympathetics doing the opposite as we returned to the horizontal. It is complicated! And the more complicated a system the greater the potential for it to go wrong. That is why I hate modern cars – I can’t fix ’em when they break down. Give me an old banger any day!

POTS due to poor energy delivery mechanisms

We know the first part of the mechanism. There is no doubt that POTS is part of poor energy delivery mechanisms because it results from the heart not beating sufficiently powerfully to maintain blood pressure. Most CFS/ME sufferers tend to have low blood pressure and feel most comfortable lying down – it is much easier to circulate blood on the flat! On standing the heart has to increase output by 20%. The heart, with good energy delivery, achieves this by beating 20% more powerfully. However if energy delivery mechanisms are not up to this, the only way cardiac output can be increased is for the heart to beat faster. This too demands more energy, and beating faster is not sustainable, and so suddenly we have very fast but increasingly weak beats and then ……… blood pressure drops precipitously. If the sufferer remains vertical they will lose consciousness and drop to the floor. See Postural orthostatic tachycardia syndrome or POTS

Having put in place interventions to improve energy delivery most POTS sufferers improve. However some are left with on-going POTS symptoms. Why should this be? Despite putting in place all interventions to improve energy delivery, the problems of POTS persists!

The Vagus nerve has become badly programmed………

The body, brain and immune system are intelligent. All can learn new tricks. Most of the time this happens correctly and is highly desirable. But when the wrong tricks are learned, disaster may result. If the immune system is incorrectly programmed, this results in allergy and auto-immunity. If the brain is incorrectly programmed this may result in PTSD. If the body is incorrectly programmed we may lose co-ordinated movements (the opposite is the case – with practice and training you could learn to play the piano!) – there is such a thing as muscle memory. If the vagus nerve is incorrectly programmed then POTS may result.

…………..because it is infected

Michael Van Elzakker has hypothesised that in ME, which is infection driven (that is to say the clinical picture is one of poor energy delivery AND inflammation), the vagus nerve has been infected and this ALSO results in POTS. Please see CFS: a herpesvirus infection of the vagus nerve?

This is biologically plausible – all the herpes viruses get into the nervous system and once ensconced there they remain for life. It is the vagus nerve that holds most of the nerves of the autonomic nervous system – the sympathetic and parasympathetics. It is these nerves which control heart rate, the power of the heart, together with blood vessel constriction or dilatation, it is these nerves which allow Tarzan to swing through the trees without falling unconscious!

And yes you all want to hear it, don't you?! Tarzan Noise

Elzakker points out that when Dr Martin Lerner treated his ME patients with the anti-viral valacyclovir, their POTS disappeared. [See Valacyclovir in the treatment of post viral fatigue syndrome and Chronic viral presence in CFS/ME.] Since these drugs are specific against the herpes viruses, and many cases of ME are triggered by herpes virus such as EBV, HHV6, chickenpox virus, CMV and herpes simplex, it seems likely that these are the infectious offenders. All these viruses target the nerves and the immune system. Furthermore the vagus nerve is well plumbed into the gut, and we know that enteroviruses are good at switching on ME (coxsackie, polio, ECHO), and so it is easy to see how the vagus nerve can get infected from the gut. Indeed it has been hypothesised that the vagus nerve is a potential conduit between the gut and the brain by which viruses, bacteria and prions can drive brain pathology.

If a nerve becomes chronically infected, what symptoms may we expect? It may over-react or under-react. It may cause pain (and many ME sufferers have “chronic pain syndrome”). Elzakker suggests that viral infections have the effect of amplifying any nervous signal. It is easy to see how this could drive POTS even when energy delivery mechanisms are improved. How so?

A virus, lodged within the vagus nerve of the automomics can cause havoc by upsetting membranes, electrical charges across them and so inappropriately amplifying nerve signals. As soon as the virus infected vagus nerve perceives vertical there is an inappropriate racing of the heart and this brings on another problem (I told you it was complicated!)

Inappropriate vagal activity may blow open a PFO

...and this suddenly reduces energy delivery mechanisms through oxygen starvation.

If the heart beats far too quickly, that alone reduces cardiac output simply because the heart does not have the time to fill and empty efficiently. Blood pressure falls AND so that alone may cause POTS. However, there is another mechanism which compounds this. It has been well described by Dr Paul Cheney. It is the problem of a patent foramen ovale [PFO] and he estimates this exists in 90% of CFS/MEs.

The detailed explanation you can find at Patent foramen ovale as a cause of fatigue

Essentially when blood pressure falls, the PFO blows open, blood does not circulate the lungs and so oxygen levels fall precipitously. Obviously this too will result in acute fatigue!

This may explain why many patients report a drop in oxygen saturation when they experience POTS.

Implications for treatment

FIRST improve energy delivery mechanisms

For many, improving energy delivery mechanisms is all that is required ie PK diet, vitamin C to bowel tolerance, improve mitochondrial function, correct thyroid and adrenal function.

If POTS persists despite improving energy delivery, that suggests there is an infection of the vagus nerve, probably with a herpes virus (most likely HHV6, VCZ, CMV, EBV HSV). In this event there is a two pronged approach:

SECOND - block the effects of such vagal over-reaction

This is where conventional medication may help – such as beta blockers, alpha blockers, midrodine and mestinon. The key point here is that the conventional treatment of POTS (for example beta blockers) will make POTS worse because these drugs (and many others) inhibit energy delivery mechanisms. This explains a mystery to me – why it was that some clearly did respond to these blocking drugs when I would expect the opposite! It was because they had put in place the energy delivery mechanisms as above.

I wondered about nicotine – this has profound, and clearly for many pleasurable, effects on the autonomic nervous system – any guinea pigs out there like to try nicotine chewing gum?

When the vagus over-reacts there may be release of cytokines. These are the immune cell-cell communicators which make us feel ill - fatigue and malaise. These nasty symptoms stop us doing things so that more energy can go to the immune system for fighting infection.

THIRD – compensate for the other effects of malfunction

  • Low blood volume – stay hydrated with a high salt diet.
  • You also need fat and water to fully hydrate. See the PK cookbook. Some doctors use fludrocortisone but licorice works similarly.
  • Compression stockings – to prevent blood pooling in the legs

FOURTH – treat the infection

FIFTH – put the vagus nerve into a “straight jacket” to re-educate it

TENs machines have been long used and are of proven efficacy in treating chronic pain. There is now good clinical evidence that these are helpful to treat POTS. Dawn has discovered another way of putting the vagus nerve into a straight-jacket – by using TENS. This is easy to do – anyone can purchase a TENS machine. Below are the links for the vagus nerve stimulation with a TENS machine.

  • The long video shows theory and results for the presenting OT, Andrea Parker, who also has ME.
  • The short video shows how to place things.
  • The article gives the settings.

Dawn

Dawn has found the TENs machine has revolutionised her life! She can remain vertical and go for short walks. Importantly her ability to do this is getting better all the time. Others are joining her and seeing benefits. WATCH THIS SPACE.

Note of Caution

Remember as with any new intervention – hold all else in place – this is as well as not instead of ………….and go slow!

Related Links

External Links


Sarah Myhill Limited :: Registered in England and Wales :: Registration No. 4545198
Registered Office: Upper Weston, Llangunllo, Knighton, Powys, Wales LD7 1SL, UK. Tel 01547 550331 | Fax 01547 550339