Saturday, December 29, 2007

Atrial tachycardia and fibrillation

Many moons ago I suffered alone as the sole voluntary victim of a major professional examination. My fellow co-sufferer was absent as he had been admitted, as an emergency, to his local coronary care unit. Some sort of severe atrial tachycardia on the eve of our vivas. Stress is not the word.

As he is both highly medically qualified and BUPA insured he got a full and frank discussion with an good cardiologist, who was neither pressured for time nor needing to talk down to his patient.

The summary was that the problem was idiopathic, would be recurrent, would probably get worse and eventually the medics would do some sort of radio frequency catheterisation to ablate or burn out some aberrant conducting tissue in his heart. Sounded like a lot of fun. In the mean time, until the problem had developed enough to warrant the burn, the suggestion was "Here, have some beta blockers to pop whenever the rhythm hits".

He passed the exam.

This was the state of play for several years. We then met up under rather different circumstances and got chatting about life in general, including cardiac rhythm abnormalities. I happened to have this paper on my hard drive:

Differential effects of high-fat and high-carbohydrate isoenergetic meals on cardiac autonomic nervous system activity in lean and obese women

The crucial line is:

"After the CHO-rich meal a greater increase in LF/HF and in plasma NE levels was observed in lean... women, while no differences were observed after the fat-rich meal."

NE stands for norepinephrine, or noradrenaline as we say in the UK. The prime purpose of taking a beta blocker is to block the action of noradrenaline (and adrenaline too, if it's sloshing around). LF/HF is an ECG derived marker of sympathetic nervous system activity.

Just occasionally you are privileged to observe someone have a "eurika" moment.

His comment was:

"That's me! It's always in the evening, after a high carb meal, especially pasta."

You can guess what a "heart healthy" diet had been doing to his rhythm problem! We chatted over lunch, he ate the cheese, ham and salad but skipped the bread. I met him a year latter. He hadn't needed to take another beta blocker.


A close family member developed paroxysmal atrial fibrillation. Again she got worked up by the medics and supplied with a script for, you guessed, a beta blocker. And told to take aspirin daily to stop blood clots forming whenever the atria were fibrillating. The aspirin gave her stomach pain and the beta blocker made her feel exhausted for the 6 days she took it. Stopped the AF though.

I generally keep my mouth shut under these circumstances, but she asked for advice, point blank. It was much tougher to sort out her AF than I had expected. Even with a magnesium supplement (just finished a stint on Weight Watchers, so probably deficient in everything) it took 4 days to stop the fibrillation attacks. I had expected it to clear up after the first LC meal, but I guess it had been on going for 2 years, so some delay is acceptable...

Why don't cardiologist read these papers?

Peter

15 comments:

mtflight said...
This comment has been removed by the author.
mtflight said...

Hey Peter,



I'd read this post before, and enjoyed it. I had a premature junctional contractions (PJC) episode one time while adapting back into ketosis after staying off for a while. I had it diagnosed as benign, originating in the AV junction.



It happened again, while returning back to low carb, not too long ago--except I knew exactly what it was this time, and it went away in a couple of days.



A coworker felt motivated by my experience and that of other people who had lost weight on low carb, and decided to give it a go starting just this past weekend.



We talked about the PSMF (protein-sparing modified fast), and he decided to try that method instead, along with low carbohydrate maintenance and single meal a day (as per So Thin So Fast, Dr. Eades' book).



So he started low carb on Saturday (to get into ketosis first), and then the sugar-free protein shakes on Monday. By Tuesday he's down almost 4 lbs. Wednesday (today) he has an "odd chest pain." He thinks he needs to go to a doctor, his wife came to take him to the doc. When he's there he gets an ECG, is referred to a cardiologist, does a stress test and ultrasound, and after a few hours he comes back to work and tells us he was diagnosed with (WPW) Wolff-Parkinson White syndrome.

So apparently when his heart rate goes up, it goes haywire, or something like that, so it is an urgent problem. 

I was astounded, and he was floored. Luckily the doctor told him it was unrelated to 3 days of dieting. 



Analysis


I think that the electrolyte imbalance and switch in metabolic paths from glucose to ketones, caused it to express itself. Perhaps the heart became more responsive while on the more efficient ketone burning... or perhaps he lost enough magnesium and potassium... either way I think this botched diet trial caused it's diagnosis. It obviously didn't cause the congenital defect, but caused it to rear its ugly head and be diagnosed.

I believe the next step is catheter ablation procedure where they zap the offending tissue so he has an appointment with a surgeon for a consult.



So I'm curious:



would his heart test back to normal on glucose? (he was likely still way in ketosis when diagnosed)



He said the pain went away after his dinner meal which was higher in carbs (left ketosis).

why did the doctor not run bloodwork to find out what the electrolyte status was.



would his WPW remain undiagnosed had he not tried the low carb and PSMF?


I’m unsure of my level of responsibility, nor how I should feel. 


Thanks for your excellent, resourceful blog, Peter.



Cheers.



Alex

mtflight said...

"Richard Veech warned against ketosis in people with pre-existing heart conditions since the elevation of free fatty acids in blood affects "the transcription of uncoupling proteins," which can induce cardiac abnormalities like unstable angina and cardiac arrhythmia."

Found this on http://books.google.com/

Hunger: An Unnatural History
By Sharman Apt Russell
Published by Basic Books, 2005
ISBN 0465071635, 9780465071630
262 pages

Peter said...

Hmmm, if you pubmed Veech and ketosis you get some interesting hits. He is obviously pro ketones and I guess he's had some problems to qualify this. It just increases my respect for JK, even though it is FFAs that Veech is cautious about. LC eating with just an edge of ketosis might just get the best of both worlds...

Peter

mtflight said...

update: friend still tested abnormal when out of ketosis. He had his catheter ablation procedure last week. There are still some anomalies to the ECG, but supposedly they will correct themselves with time. Outpatient procedure, but he's at home resting for at least a week.

In retrospect, I noticed when I was having PJCs (skipped beats, much like PACs or PVCs but originating in the AV junction) a couple of times, it was while starting low carb.

I've been exercising sometimes in ketosis and sometimes felt the PJCs. So I started adding a potassium salt substitute in my water, and the PJCs disappeared.

I think it may not be the ketosis triggering them necessarily, but rather the electrolyte loss that is more marked when insulin plummets (as during ketosis). So now I drink some potassium in my water (just a sprinkle here and there), and no matter how intense the ketosis and exercise, no PJCs.

The heart becomes hyperexcitable when low on K, and that could lead to these nuisance arrhythmias.

on Eades' book on PSMF (So Thin so Fast), he mentions to get the doctor to do an electrolyte test and a baseline ECG (among other things).

hopeful geranium said...

Thought you might be interested in this. Us lean types may not need quite as much vit D as the average citizen, and atrial fibrillation might be one sign. Probably from the calcium/magnesium balance shifting, I suspect.
"For a column that has spent some effort to advocate for Vitamin D and its benefits, it’s important for us to also know where our upper limit is. What is toxic? I get that question all the time and we haven’t had a clear answer. Now we do! It’s atrial fibrillation that emerges as the risk. A recent study found that folks with an excessive level of Vitamin D, greater than 100 ng, have a two and a half time increased risk of developing atrial fibrillation. The study has pretty good predictive power because they were following some 132,000 people"
http://www.healthy.net/scr/Column.aspx?Id=1294

John Atkinson said...

Indirectly, couldn't excessive CHO intake cause a-tach/fib. by damaging the vagal nerve? I know vagal neuropathy is a relatively common facet of diabetes. That play a role?

Mandy Hoff's E-Portfolio said...

This article was very interesting! I've been doing some variation of low carb for the past 2 years or so with no problems. However, since going pretty strict low carb/high fat 'paleo' I notice that whenever I cheat with something very high in carbs I feel an unsettling fluttering in my chest for a few minutes. I self-diagnosed it as some type of fibrillation, and searching for more information about it led me here. I'll stick with lower-glycemic carbs, or at least eat high glycemic carbs with lots of fat to slow absorption so I don't feel that anymore.

As far as electrolyte imbalance is concerned, maybe it gets out of whack when consuming carbs because of the resulting water retention? Perhaps it could go both ways. Rapidly switching from carby to fatty or vice versa may mess with you enough to throw electrolyte balance off. I don't know enough about that subject, but I would love to hear your thoughts.

I don't know about Vit. D being the problem. How would one overdo that exactly (aside from taking a bottle of Vit D supplements)? I don't know enough about Vit D synthesis, storage, and utilization in the body to be an expert, but I do know that being in the sun one can make a ton of it. I've never heard of someone having fibrillation from a sunny day. According the the admittedly unscientific http://www.healthdiscoveries.net/vitamin-D.html, one can produce 10K IU of Vit D in 15 mins at high noon, which, according to the article cited in the previous post, is enough to bring blood levels to 80ng. On my 1 hour lunch break at the height of summer, I would be making quadruple that! The body must have some regulatory mechanism, or perhaps it can handle more than we think. I also remember reading somewhere that tolerance for Vit. D goes up significantly when taken in conjunction with Vit. A. Perhaps this too is a balance issue? More research needs to be done. As always!

Anyway, I love reading this blog and its resulting comments. Thank you for posting and offering intelligent and insightful viewpoints to this complicated and fascinating subject! I look forward to learning more from all of you.

Verleen said...

I have had AF for 5 yrs, controlled by two different medications. I also have type II diabetes controlled by oral medication. My Afib starts mostly in the evening, but occasionally in the morning. It had been under control without any prolonged episodes for over a year although I have had some jumps. In the past month I have had three major episodes lasting from 8-11 hours. I had an ekg, complete blood panel, all came back with excellent results. I am thinking of seeing an Endocrinologist, but am skeptical as to what he can do for me. I truly believe it has do with diet and possibly my electrolytes. I take magnesium and other vitamins, but am becoming very depressed that my Afib had started up again. When my blood sugar level is below 70 my changes are great for Afib, if my levels go above 150 I may go into Afib. I am wondering if low-carb dieting is the solution? Anyone have suggestions? Should I see someone for a complete electrolyte work-up. What if my electrolytes are normal at testing??

Verleen said...

I have had AF for 5 yrs, controlled by two different medications. I also have type II diabetes controlled by oral medication. My Afib starts mostly in the evening, but occasionally in the morning. It had been under control without any prolonged episodes for over a year although I have had some jumps. In the past month I have had three major episodes lasting from 8-11 hours. I had an ekg, complete blood panel, all came back with excellent results. I am thinking of seeing an Endocrinologist, but am skeptical as to what he can do for me. I truly believe it has do with diet and possibly my electrolytes. I take magnesium and other vitamins, but am becoming very depressed that my Afib had started up again. When my blood sugar level is below 70 my changes are great for Afib, if my levels go above 150 I may go into Afib. I am wondering if low-carb dieting is the solution? Anyone have suggestions? Should I see someone for a complete electrolyte work-up. What if my electrolytes are normal at testing??

Peter said...

Hi Verleen,

Anyone putting their blood glucose above 150mg/dl is in trouble, AF among many other problems. There is no solution to to T2DM other than LC... Sad but true!

Peter

uk mike said...

Hi Peter,
I to have had an experience whilst on a low carb diet,I had cut out carbs to almost nothing eating only lean meat,eggs and green vegetables.
I have had angina for 8 years but during the first week of the diet the angina all but ceased but I noticed an increase in my resting and exercising heart rate also I felt that I had more energy and alertness,I was losing about 1.5lbs a day this is great I was thinking until the end of the second week when my heart started to flutter and beat irregularly at first then increased to 140 bpm at 3.00 in the morning,not good.
I called the out of hours service and was admitted in to hostpital but by the my heart rate had returned to normal on my arrival.
They carried out ECG,Xray and blood work and diagnosed Artial Flutter and said that it was nothing to do with the low carb diet but more likely age related( I am 56),they also told me to double my Atenolol to 50 mg,this I did once only and returned to 25mg.
When I got home I did some research
and found some articles that suggested a link between AF and low carb diets armed with this new information I took a supplement that is used to replace salts etc following a bout of diarrhoea and I then introduced some complex carbs and a little fruit into the diet and I have gained only 2lbs in the first two weeks,this weight is being maintained,no AF, very little angina and I feel good.

UK Mike

Peter said...

Hi Mike,

Your story is reminiscent of a number of other reports when people have gone on modified protein fasts. These are rapid weight loss diets, low in fat as well as carbohydrate. Most people feel crap on them, rather than good, and sympathetic nervous system overdrive appears to feature as part of the problem. Personally I would eat much more fat, slightly more starches and definitely dump the fruit...

You have to wonder whether the drop in insulin is not enough to deliver adequate calories, so the body ups the sympathetic nervous system to increase lipolysis, cardiac tachyarrhythmias being a possible spin off. Dunno, but it's a thought.

Peter

Vicky said...

I had atrial fib that increased in severity over a 5 year period and ultimately necessitated 2 catheter ablations at Cleveland Clinic. It has not returned. I kept a journal and found that certain foods are triggers. A big one is alcohol. I enjoy good wine. Even in moderation it would be a trigger. High carbs and dark chocolate another. Electrolyte imbalance is certain to be an issue. My fib was known as lone atrial fib, thought to be extra conduction tissue I was born with. The longer one stays in fib, the more episodes will happen. Sometimes it would last for 3 days! I do a lower carb paleo type diet and have been free for 10 years now.
Vicky

Vicky said...

I suffered from atrial fib for 5 years which necessitated a catheter ablation twice. The more you stay in fib, the more episodes tend to increase. Keep a journal. Triggers tend to be alcohol, dark chocolate and high intakes of refined carbs. I eat a lower carb, not more than 120 grams per day, paleo diet. I have been fib free for 10 years now.

Vicky