Simplifying the complex vagal issue

[WendyWu20]

I've spent the last few days reading through past posts on the vagal issue in AF, and researching online. But I can't seem to get a clear, simple concept of how exactly, the vagus nerve contributes to starting and stopping AF!

I understand the basic 'vagus nerve slows the heart rate' concept. Also, that a 'high' vagal tone is thought to be a good thing, as it improves the function of many body systems.

However, there are posts and online articles that promote both vagal calming AND increased toning. This is my first area of confusion, which then leads to more befuddling when I read about AF being triggered by either a slowed heart rate (well-toned vagus nerve), or by ectopics and tachycardia (low vagal tone).

So I am reaching out to any lovely people out there, who have managed to attain a coherent understanding of these processes! Thank you in advance :o)

[BobD Volunteer]

Yes this is a complex problem. The "expert" who I learned most of my stuff from merely said that AF was more likely when the vagal tone was low. In other words when you are resting and your heart rate is low.. Many people therefore find that their AF starts during sleep or after a large meal.

I'm sure you understand that the vagus nerve is the body's neural superhighway between brain ., heart, stomach and several other organs. Since there can be feedback it is obvious that what affects one can affect others.

Basically that is all one needs to know if you happen to be one of those people who's AF is vagally mediated. For many people this is a non event and it is true to say that until recently many EPs did not accept the role of the vagus nerve in AF. AF is such a mongrel condition that there is no common denominator I'm afraid. It would be very interesting to see a study showing the percentage of people with AF who ARE vagally mediated but a rough idea from this forum would suggest probably less than half but more than a quarter.

[WendyWu20 in reply to BobD]

My nursing background tells me that the (twin) vagal nerve has about 50 main branches to separate organs/areas, with many more smaller branches. Specifically, it releases the neurotransmitter acetylcholine onto the heart's sinus node and allowing the heart rate to slow. That's the simple bit :o)

But I think a confusing element for me with this issue, is the phrasing and terminology used. For example - vagal 'tone', I find vague. In addition, people use opposing terminology (either high/increased tone, or low tone) when describing exactly the same process of vagally mediated low resting heart rate.

[BobD Volunteer in reply to WendyWu20]

The Professor uses "low vagal tone" for slow heart rate/ sleep/ resting which is good enough for me. Never heard of it the way you described. It would be counter intuitive to have low meaning fast.

[CDreamer]

Wendy I posted a link to a YouTube presented by neurologist which explains ANS very explicitly - yu have to watch to near the end of the video to get to the bit that explains vagal and the Heart.

[Spud12345 in reply to CDreamer]

Could you send me the YouTube also? I think I have vagal mediated a fib-happens at night. No cardiac issues other than a fib

[CDreamer]

Don’t know if you have already seen it but I found had this the clearest explanation I have seen and helped me understand it more.

healthunlocked.com/afassoci....

[CDreamer]

PS - as I have a neurological condition as well and both conditions concern Acetycholinen and intake an Acetycholineneterase I am always looking for links between the 2 conditions - and finding a few which helps me manage both conditions.

My AF is triggered by tachycardia so calming my vagus nerve is essential for me, especially after eating. But lying supine also triggers Dysrythmias which I suspect was caused by low vagal tone and l know my HR can dip to low 50’s at night.

Vagal tone can be measured by calculating HRV - heart rate variability - this comes from sports sciences as many elite athelete will tell you as so many can get a bit obsessed with it. Kardia used to record HRV but most people didn’t like it because they didn’t understand it and got concerned so the facility was removed from the app.

HeartMath are the only organisation who seem tonavendone solid scientific study around this and have some good information.

heartmath.org/?s=Heart+rate...

[WendyWu20 in reply to CDreamer]

Thanks, the HeartMath people do some interesting research :o)

[secondtry]

On a more simplistic level, I have acted on a mixture of reading here and elsewhere and my experiences. Although I agree with you it would be nice to be clinically clearer.

I deduced I was vagally mediated and that the main issue was my calming mechanism (parasympathetic I think) needed to be under-utilised for a period (to detone it, using a muscle analogy). After 3.5 years of avoiding as much stress as possible and with Mindfulness etc things are much better and I think my sympathetic and parasympathetic are now back to a more normal equilibrium. Part of this process was not having AF for 3+ years , which in a vicious circle was itself creating more stress and winding up my parasympathetic system.

[WendyWu20 in reply to secondtry]

Glad you've worked out a way of keeping your body in balance :o)

[secondtry in reply to WendyWu20]

Thanks, I think it is called persistence rather than intelligence! Have a great day.

[LindaDaisy]

I found a little book free on kindle unlimited called Heal your vagus nerve, heal yourself which seemed quite useful. It recommended singing or humming to improve vagus nerve tone. Well I've had no AF for several months but my husband is being driven crazy by me humming all the time. lol

[WendyWu20 in reply to LindaDaisy]

Yes - me too, I'm half way through it. I recently blotted my copybook by humming The Dambusters theme, when we were watching Only Connect haha :o)

[ian16527]

When I first had a problem with ectopics, coupled with ache in the chest and pain on extending the chest muscles, I was took to CCU where they said I had costochronditus and kicked me out.

The GP who I saw said that was not the case and was probably down to the Vagus nerve but said no more. This was in 2010. Unfortunately she left and now when I mention this I get looked at as if I have 2 heads.

The AF started 2 years later, but with the same symptom's as above initially.

My AF started(2 out of 3 times) when I was dropping off to sleep, and coupled with a meal(3 out of 3 times).

Also, 30 years ago when I was in ITU after major surgery, the nurses used to get concerned as my heart rate would drop to low 40's when asleep, which seems to be connected as well.

[destept]

I have afib and I use emWave program in hoping to balance my autonomic nervous system.A very interesting biofeedback program for heart rate variability.

[WendyWu20 in reply to destept]

Ooh that sounds intriguing :o)

[CDreamer in reply to WendyWu20]

Expensive - heartmath.co.uk/shop/

[CDreamer in reply to destept]

I think that is the HeartMath one? I had one of their first devices you attached to a smart phone and I loved it as it gave various readings of HRV but unfortunately when the iPhone changed their connectors it no longer fits.

[destept in reply to CDreamer]

No, it is a program called emWave that you use a disk in the computer and a clip for your heart rate.

[CDreamer in reply to destept]

Yes, emWave is produced by HeartMath. They have various versions.

[secondtry]

Hi Wendy again, this just came up on my Twitter feed re the Vagus Nerve, thought you and others might be interested cdn.theheartysoul.com/wp-co...

[LindaDaisy in reply to secondtry]

The first one, splashing your face with cold water is one of the vagal manoeuvres. It stimulates the diving reflex. It's one of the methods I use to try and stop a fast arrhythmia. The rest of them make sense to me.

[secondtry in reply to LindaDaisy]

Hi Linda, yes it is quite amazing how the body sends messages to deal with issues. I have found for a long time after cleaning my teeth at night that it made me feel better to splash my face with cold water, just thought of it as a habit I picked up for no reason. Now when I think my Vagus Nerve is functioning better, I notice I do not have the same urge to splash my face . Every day is a school day!

[Mercurius]

There is very simple animal experiment. The heart has both vagal and sympathetic innervation. If you stimulates both the vagus and the sympathetic cardiac nerve equaly even the healthy animal starts to fibrillate.

The balance of this double innervation controls our heart rate and blood pressure. In the case of high or low vagal tone the adaptíve response of the sympathetic cardiac nerve will exert the same intensity of stimulus as vagus (in the first case in order to compensate the elvated vagal tone, in the second case not to owercompensate the low vagal tone).

What can we do?

Basically the high adaptive response of blood pressure or heart rate is requiered when we are under stress. I use for controling this response "yoga training". With appropriate heart rate or pulse rate sensor I make exercises to minimize my heart rate change upon stressing circumstances (noise, quarels or even haevy metal music).

Mercurius