Abnormal Vagal activity

[PVC]

Hello and I appreciate the opportunity to ask a question on this busy forum.  My story is one of heart arrthythmia that I believe results from increased vagal tone.  I am only 38, male and in otherwise perfect health except for this atrial arrhythmia.  You may be wondering why I am bothering to ask questions in a neurology forum but I have exhausted the cardiology testing including a trip to the Mayo clinic where some peculiar results were found.  First of all I am the only person that apparently has the connection between swallowing and a heart arrhythmia.  My heart will beat normally until I swallow.  Everytime I swallow there seems to be a short pause followed by a burst of atrial tachycardia.  This has on several occassions degenerated into afib.  All the cardiologists have never heard of such a strong correlation with swallowing.  I understand that the vagus nerve passes behind the esophagus and is responsible for many things in our body.  Vagal stimulation exhibits a parasympathetic effect on the SA node of the heart.  When I swallow it seems that the heart beat pauses and then becomes arrythmic for a few seconds.  If I do not swallow nothing goes wrong - the correlation is perfect.  When I run my heart rate will be 140 bpm with no problem until I finally swallow.  I have seen the heart rate jump to 239 bpm right after the swallow.  So to sum up I have done all the cardiac investigations including an EP study, which showed nothing abnormal.  I apparently am the only person that shows the swallowing trigger caused by the vagus nerve I believe.  Can you help me understand why this happening.  I appreciate the cardiac angle completely.  But the cardiologists are baffled as to my swallowing trigger.  At first they didn't beleive it - called it a coincedence.  They now recognize it as something unique but really don't know where to go with it so I am treated as all other afib patients.  An electrophyisologist recommended I try scopolamine to see if by inhibiting the vagal effect I could minimize or eliminate the problem.  I have not done this yet but did notice that during a recent cold my resting heart rate went from 50 (normal for me) to 70.  During the days with this higher resting rate the swallow trigger disappeared.  Are there medications that can do this on a permanent basis?  Are there procedures that can correct a hyper active vagus nerve.  Or is there another possible explanation for all of this.  

Sorry for the long response but details are important.  

I appreciate any ideas you may have.

Peter

[CCF Neuro[P] MD, RPS]

Dear Peter:



Sounds too interesting to be true.  I guess you could just stop swllowing but that would be too easy.  I have one problem with your theory.  It sounds very convincing.  However, the vagus does more than just swallow.  Since this does not happen when you have a bowel movement (a classic valsalva maneover) should do the same thing and evidently it doesn't.  This would also produce a parasympathetic output.  I might just give a trial of what the EP specialist suggested.  If it controls your problem then you are in luck and they have a publication.



Sincerely,



CCF Neuro MD

[Peter]

Thank you for your thoughts.  I wasn't sure if you would laugh me off or see this as an interesting and unique case.  Your observation regarding the bowel movement is accurate, however is it not possible that the specific fibres being stimulated by the action of swallowing could create  the problem?  I did not mention before that because of this connection I asked for a barium swallow to see how the esophagus looked.  They found significant acid reflux which was then treated.  The problem seemed to go away for a while and then return.  I thought that was the answer - chronic irritation of the esophagus had finally affected the vagus nerve, which upon swallowing, did its thing to the heart rhythm.  Unfortunately even while on the reflux meds it returned.  I guess the problem for me is the fact that the empirical evidence is conclusive - I swallow I get a momentary arrhythmia that unfortunately can degenerate into afib. Every test on the heart is completely normal, which is of no surprise in that I have run marathons, climbed mountains and kayaked at 5 whitewater nationals.  The fact that even the cardiologists can't explain this and that they actually have never heard of this but see that it is happening, makes me all the more convinced of finding a solution.  I believe that, although I have been cast into the pit with all other heart patients that in my particular case something else is the cause and that if it could be idenfified perhaps I wouldn't need to suffer years of trial and error medications etc.

I guess it is my hope that someone will eventually either recognize something or become interested enough to pursue this - I guess I can join the club on this line of thought.

Any other ideas, suggestions?? Perhaps from the neurologic point of view there could be test, medication worth trying?  As for the scopolamine what do you know of this drug? I believe it is taken for motion sickness for a few days only.  Is there a drug out there that could do the same thing but indefinitely?

Always searching!

Peter

[CCF Neuro[P] MD, RPS]

Dear Peter:

It is always possible that there is segmental vagal dysfunction but the overwhelming evidence of the literature would be against it.  However, your symptoms are not your everyday ones either.  Reflux really has not too much to due to vagal nerve innervation of the anatomical spincter of the eosphagus.  The vagus can cause too much acid secretion and subsequent gastric ulcers.  However, you would certainly know this as this is a very serious entity that needs surgery to clip the vagus.  What doesn't sound right to me is that an acute brady would induce tachycardia.  Sinus tachycardia that is narrow wave (SVT-like) is actually treated with vagal stim.  It is also treated by adenosine which actually stops electrical transmission (the ultimate brady) for a brief moment to kick the heart out of SVT.  So you are really a paradox.  I am sorry I can't help.



Sincerely,



CCF Neuro MD

[Peter]

Your observations are appreciated.  With regards to the acid reflux, how about the idea that esophagitis could in fact irritate the vagus nerve enough to cause the vagal brady upon swallowing.  Such a momentary effect could initiate the SVT and ultimately afib.  Cardiologists due recognize that a sinus pause can trigger such events.  So in closing I would first like to say thankyou for you time and thoughts.  I would also ask - at this point in time it would appear that such ideas are not supported in modern medical thought so I suppose I am confined to pursue this from the cardiac viewpoint.  If I were in a hospital such as yours would there be testing and possible treatment from a neurological point of view?

Peter

[Peter]

One other symptom worth mentioning - it seems that prior to the onset off heart beat problems (ie. swallowing trigger) I experience a fair amount of muscle twitching especially in the left Pectoralis muscle group.  I sometimes wonder if the twitches are in fact skeletal or cardiac in origin.  There is no disruption to the beat so I suspect it is skeletal.  Could this entire scenario be part of a neuromuscular disorder of some sort?

Peter

[CCF Neuro[P] MD, RPS]

Dear Peter:



The right vagal nerve control heart rate, so left pec twitching will not be involved.  In addition, the pec nerve comes off the brachial plexus and not the vagal nerve.  Yes, severe irriation of the eosphogus can cause neurological symptoms: Sandifer's syndrome.  However, the irritation is severe and one would see seizures in this disorder.  I think that cardiology would be the ones working you up for this, but the answer is yes.  Why don't you contact the cardiology site on this service as they are from the Cleveland Clinic.



CCF Neuro MD

[brian]

HI Peter -



I also suffer from PVC's PAC's (I feel these every day - some days only a few and some days hundreds). I have also had several episodes of atrial fibrillation that lasted for hours. In addition, I have frequent episodes of elevated heart rate. I have had multiple echos and  stress EKGs and all tests are normal.  Doctors say not to worry and just to live life.



Although I have never noticed symtoms when I swallow, I have noticed a strong correlation between eating/indigestion and "skipped beats".  My doctor doesnt understand this, but nearly every time I have gone into afib (about 5 of 7 times), I was drinking/eating something very cold. I have also noticed syptoms are reduced when I take an antacid or Prilosec for my stomach. These are definite correlations and ones I am not imagining.



I too have a lot of (what feels like) muscle twitching in my chest (in the muscles over my rib cage). Muscle twitches are common elsewhere (legs, feet) too.



So you are not alone.



Brian

[CCF Neuro[P] MD, RPS]

Dear Brian:



What you are experiencing with eating or swallowing something cold is a vagal response.  This is a technique we use to stop someone in SVT.  What happens is that the cold solution induces stimulation of the vagal nerve by causing a sudden change in the