Vagus nerve

I have a question about the vagus nerve - if that becomes damaged, does that mean that the heart rate remains the same with exertion?

I get sinus tachy and today it was way up just from moving.  It was a nice steady rhythm then when I sat up in bed from being in laying down position it raced up to about 180 or so, it was crazy, I almost fainted.  I then got up and came downstairs, taking my beta blocker.  Within half an hour it was back down to about 100 then to about 90 ish a few minutes later.

Would vagus nerve damage cause it to go up and down, or would it be in the same tachycardic rate even on exertion?

I have neuro symptoms also.  

[anacyde]

The vagus nerve can regenerate.  Damage to it is unlikely.  I would look to a different possibility...

[quillswriting]

If there was pressure or a lesion on the vagus nerve, would that cause tachy?

It is odd because I have read that its damage means that the rate does not change, it can be elevated but not change on exertion.

Is that true?

[fwilson3]

anacyde:  "The vagus nerve can regenerate.  Damage to it is unlikely."

Where did you get this information?  The vagus nerve does not regenerate particularly better than any other nerve in the body as far as I know (and that is not very well).

As for not getting damaged, it is fairly internal, but its long length would argue toward it having relatively many possible injury locations.

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As for quillswriting's heart rate variability, At heart rates under 100, the vagus nerve is MOSTLY controlling the rate.  MOST of the variation you see in heartrate below 60 is vagally mediated.  By the time your heart rate hits 100 and above, it is mostly controlled by the sympathetic nervous system.  Incidentally, since a denervated heart beat very near 100 bpm at rest, it can be demonstrated that most of the time, the vagus nerve predominates heart rate control.  When people lose heart rate variability (beat to beat changes in heart rate) it is MOSTLY due to a lack of vagal influence (meaning the heart rate averages higher than it should because it doesn't slow as it should).

Quillswriting, will your heart slow to normal at rest just before sleeping and so forth?  There are many reasons for a fast heart rate.

[va_tony]

Quillswriting

Here's an exerpt from a CC Cardiologist's anwer to a similar question:

"CCF-M.D.-MJM
2/27/2006
duchess47


2. Will vagus nerve damage cause heart rate changes?

It can. Typically damage to the vagus nerve may decrease parasympathetic tone and allow increases in heart rate. "

Because the vagal nerves snake though so many organ systems, I would imagine that you would also display other symptoms besides a fast heart rate if one/both of the vagal branches were damaged; for example, GI problems, voice harseness, difficulty swallowing, etc. What are your neuro symptoms?

There are two vagal nerves. The right vagus influences the sinoatrial node. Excesive stimulation of the parasympathetic predisposes bradyarrhythmias. The left vagus when over stimulated predisposes the heart to AV blocks. I think I read that both have to be damged before one sees persistent high heart rates.

It's possible that you may have a dysautonomia, where the autonomic nervous system (including the sympathetic and the vagal systems) are slightly malfunctioning. I suppose that's a form of vagal nerve damage.  Arrhythmias such as IST and POTS have an ANS basis and are common in young adults who tend to grow out of it in their 30s.  Have you ever had a tilt table test? Do you have diabetes or GI problems?

[quillswriting]

I have a number of neuro symptoms, but also have GI problems to the point where I burp a lot after eating and drinking.  I do have trouble swallowing food, it seems to get stuck sometimes.  I also have severe fatigue, pain in my arms, legs, neck and abdomen.

When on the beta blocker it is about 60-70 at rest and rises up to about 90 when I get up and walk.  Without the beta blocker it has varied, it can be about 90-100 at rest and can go right up to 180 when I walk.  Yesterday morning, before taking my beta blocker it was slow and steady while I was in bed then when I sat up it raced way up to about 180 ish and I felt slightly faint.  This morning I took my beta blocker before getting out of bed but didn't wait long for it to start working, I got up slowly, very slowly and it remained steady until I walked down the stairs.

I get pain in my hand on my right side when I type, I also have brain fog at the moment, typing and saying the wrong words.  

I have only just managed to see a cardiologist - he just took my BP and sounded me then told me to wait for a letter in the post about my echo appointment and 48hr holter.  I have also been told I was referred to a neurologist, but again, I have to wait for the letter then wait for the appt.  It took over a month to get the appt with the cardio.  I'm in the UK. I get worse by the day also, I am having some real troubles, I have been to A & E three times, we had to call an ambulance yesterday but they checked me and said my GP had to see me.  I went to see him and he told me to WAIT for the letters!

Question is: How could I have damaged the vagus nerve?  Can severe anxiety cause that?  I am terrified that I may have a brain stem tumor!  My neck has been twitching at the back a lot, though i have had the neck twitch thing when I am tense.

[va_tony]

"Question is: How could I have damaged the vagus nerve? "

While the nerves COULD be damaged by GI problems, I really doubt you have a damaged vagal nerve ....simply because your heart rate returns to normal at rest.  If the nerves were damaged, the heart rate would always remain high. I really don't don't think you have a dysautonomia either. Likely you just have something like acid reflux.  Besides giving you GI problems it also temporarilly lowers vagal tone, causing the heart rate to go up from time to time and can also cause arrhythmias (like PVCs). Acid reflux is easily treated with a proton inhibitor like prilosec. Fortunately, you'll soon see a neurologist and a cardiologist and they can either begin treatment or put you mind at ease.  I think that anxiety is also plaing a role here... anxiety tends to elevate heart rate.  Try to relax and concentrate on family, friends, work and activities you like. Take your mind off the GI and high heart rate.

[fwilson3]

Not to be abrupt, but neither a cardiologist nor a neurologist would know a vagal nerve injury if it came up and bit them.

I have just seen a top autonomic specialist as well as a top electrophysiologist and both agree that vagus nerve injury is not even considered in a differential diagnosis because: a. They cannot test for it, nor visualize it short of exploratory suregery and "getting lucky". and b.  If found, they cannot fix it.  Even in people with clear dysautonomia, vagus nerve injury is not considered for these reasons.

[quillswriting]

Before the neuro symptoms I was getting the tachy.  It was pretty much on-going, it would sometimes slow down to 90 resting, sometimes 100.  There have been occasions in the past where it slowed to 80.  It was all over the place.

Last night (bearing in mind this is while on beta blockers) after eating it was up to about 90.  It stayed like that when I was in bed trying to get to sleep.  Then, I got a sharp headache above my forehead to one side, my vision was shaking and my eye felt weird, my vision was filled with "static" and I jumped out of bed and put the light on, the vision problem stopped and my heart was pounding.  I have had pressure sensations in my head all day in various parts of my head, sometimes my neck, sometimes the top, sometimes the side above my forehead, and sometimes in my sinuses.  The rate was steady until I had some food.

I've also had alternating pupil dilation, i.e. one is dilated one day and the other is dilated the next.  I have been seen by a doctor who is not concerned as they reacted well to light, I had my reflexes checked and I was sounded.