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