PAF and temperature

[arthur]

I have had a successful rf ablation for PAF about 3 years ago. Some PV foci were left unattended, as they were found to primarily result in PACs.  Before the ablation, I was prone to trigger a PAF event by either adrenaline-inducing activities such as sudden excercise (as in playing soccer) or a cold drink while I was still hot from exercise.  After the ablation, I could not induce PAF with exercise, however, over the past three years I have had three odd events lasting 5-15 minutes each.  Two cases were triggered by a cold drink after exercising (while my body was still relatively hot), and one case by a very cold shower (again, while my body was still hot from exercising).  In all three cases, the arrhythmia was reminiscent of AF, ie, lots of apparent PACs, with few periods of regular rhythm, so it was difficult to figure if it was PAF or just a bunch of PACs.  In all three cases, the arrhythmia broke down after about 10-15 minutes.  I take no drugs.

Two questions: (1) what is the mechanism by which a sudden downward change in temperature can cause such a burst of PACs and/or PAF? and (2) does this condition warrant any treatment?

Please be as "scientific" in your explanation as possible...I am trying to understand the issue, so that I can avoid the recurrence.  I am extremely athletic (although, at 56, I might be over several hills by now), playing competitive soccer in the 40+ and open leagues.  I suspect that at least one focus is at the root of the problem, and I also believe that the problem is not a big one...I am just very curious.


Thanks,

Arthur

[Cleveland Clinic]

arthur,

While immediately quenching your thirst, the relative change in your core body temperature after exercise isn't going to change markedly, (probably less then 1 degree) so Im not sure if the two are related.  There are alot of factors at work with exercise that probably are more likely related such as adrenergic tone.

I would try to figure out what the rhythm is before making any treatment recommendations.

Overall, you are probably right about the problems impact. You are certainly more active then most in the general population and I would encourage you to continue to do so.

good luck

[hbp702]

With a doctor's permission, you could try to induce the arrythmia while wearing a Holter or event monitor.

[arthur]

I was hoping for a more detailed answer...the temperature thing is often cited by others as a trigger for PAF-like events.  In my case, I clearly got PAF from a cold drink twice (documented) before the ablation procedure.  These days that same cold drink appears to trigger an "almost PAF" event...the nature of the arrhythmia is not as important to me as the mechanism by which it occurs...besides, the earlier events were indeed PAF and they were indeed caused by a cold drink while I was still worked up from exercising.

I can imagine that the cold liquid flowing through the esophagus is close enough to the back of the heart and the PV foci to do something very special, either directly to the focus, or indirectly to the nervous system surrounding the focus, or both.

A disappointing response.  

-Arthur

[va_tony]

There have been studies suggesting a link between GERD (acid reflux) and arrhythmias.  While your case obviously doesn't involve GERD, the mechanisms may be similar.  In GERD, the esophagus apparently goes into spasm and applies pressure to the nearby vagus nerve, which in turn slows the heart rate and induces PACs/PVCs/PAF in those susceptible. This is speculative but your drinking the cold water may initiate a smilar esophagael spasm and cause a similar subsequent vagal nerve/heart response. [Note: This is not my theory.  I've seen it mentioned on several other forums to explain the cold drink trigger.  Likewise, there are theories involving the autonomic nervous system and the cold shower trigger]. Some sources claim that there is also a vagal form of arrhythmia that's fairly common in men and atheletes.  It's apparently quite common for vagal afib sufferers to experience an episode well after intense exercise. Also, athletes are more prone to A-Fib in general perhaps because they have larger hearts where there is more room to support the mutiple reentrant wavelets needed to sustain afib, and possibly because of the extra pressure they put on their pulmonary veins through aerobic exercise. The pulmonary veins are a frequent source of stray electrical signals leading to PACs. As I said this is all somewhat speculative since there have been no formal studies to delineate the precise sequence of events following the drinking of a cold glass of water. It's likely Doctor BKJ wanted to base his answer on firm science and so avoided such speculation.

[Gaspipe]

From the information you provided the Doc's response was appropiate. The benefits of this forum should be taken as information that allows the questioner to return to his Doc with followup questions or confirmation of particular issues.As the responder before me mentioned speculation without facts is inappropiate in my estimation.If you want detailed answers to your questions from the Cleveland Clinic you need to gather your medical files and records and go for a consult.Then you 'll get the best of all world's.Good Luck

[arthur]

Thanks for clarifying the purpose of this forum.

When I stated "exercise", "cold drink" and "PAF," I didn't think there was much left for speculation.  It's entirely possible that the speculation is in the explanation, so I do understand the good doctor's reluctance to provide same.  Thus, the "disappointment" is in the lack of our understanding, not in the response itself.  

BTW...I do believe I am entitled to be disappointed...it may be a fundamental right!


-Arthur

[Cleveland Clinic]

arthur,

There could be any number of 'scientific' but still speculative responses, even based on the specifics you mention.  Without hooking you up to monitors and sticking you with needles, or looking at a monitor of the event, explanations are purely conjecture.  In that case, the more specific I would try to be the more I would be BS'ing you.

The most plausible overall etiology to your symptoms would be an increase in vagal tone on the heart in both situations.  A drink or food in the stomach increases vagal tone, as does cool water in the face from the shower, which both could have triggered the same response.  

Whatever the etiology, the recommendations are as above.  

good luck

[arthur]

Thanks for the follow-up.  Being a scientist in the drug discovery arena, I am quite used to speculation and hypotheses, so I take it for granted that it's ok to guess at a mechanism.  But, given the potential gravity of anything you as a doctor may say being taken as gospel, I can appreciate your point of view.

I suspect a vagal tone scenario is at play...in each case the focus responsible must have been firing quite rapidly and strongly (through exercise), and when the cold turned up the vagal tone (slowing the heart rate) it provided an easier path for the focal noise to travel through cardiac tissue and disturb the now slower sinus rhythm, resulting in a temporary arrhythmia, the nature of which appears to be PAC-like.  (My theory)

-Arthur

[hydrocool]

I had such an episode two days ago. I farm and came in for lunch. It was hot and so was I. I opened a cold drink from the fridge and took several large gulps. I immediately got a trmendous pain in my chest and felt weak. I sat down in a chair leaning forward on my knees and then I passed out backwards onto the chair behind me. My mother, who is also a nurse grabbed me and I came to almost immediately. My sisiter-in-law, who is also a nurse was summoned and they took my BP. It was 147/96 but my pulse was 41.

I took an aspirin and went to the hospital. I had an ECG and blood work done. My BP settled at 140/70 but my pulse remained low at abot 44.

Yesterday my pulse was still low and my BP was still 140/70.

I am very active and I exercise vigorously for abot 45 minutes every morning either biking or walking/jogging. I am a 54 year old male, non smoker, 15 pounds overweight by my standards.

This has happened to me once before, also on a hot day, about 15 years ago. That time I had to lay down on the kitchen floor for a few minutes until I felt like I was back to normal.

I believe I read an article in the Readers Digest about this exact event but do not remember when.

I do not know whether this should be treated as a heart event or a single isolated event.

Does anyone have any similar experience and what do you do about it?

The doctor that treated me wants me to go for a stress test etc.

[arthur]

This may not make it to you, as I suspect the posting will disappear shortly.

The passing out thing has never happened to me.  But it does sound like a "cardiac" -related event.  The cold water will increase the vagal tone, and decrease the heart rate.  Perhaps, in your case, the decrease is abnormally abrupt.

Since this has only happened once or twice, I would avoid sudden cold drinks when your particularly over heated from exercise.  Unfortunately, I am not an expert...only a victim who's been trying to learn the why's.  I would suggest talking to an EP or cardiologist, and see what they have to say.  It doesn't sound particularly dangerous, but it would be nice to know why and how to avoid it in the future.

Good Luck

-Arthur