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by JshWright 4977 days ago
> I can't accept that this guy really was in perfect health;

I guess that depends on why you mean by 'perfect health.' He may very well have been in perfect health by every outward appearance. There are a large number of surprisingly minor things that can make you dead in an instant.

A brief primer on electrocardiology... Each heart beat is divided into several phases. An electrical impulse in generated in the two small chambers at the top of the heart (the atria), causing them to contract. This is the first small bump in an EKG, and is called the 'P' wave. After a brief pause, the impulse is conducted to the big chambers at the bottom of heart (the ventricles), causing them to contract. This is the big wave on an EKG, called the 'QRS complex.' After that, there's a period of time where the cells in the ventricles are recharging. This is the final bump in the EKG, called the T wave.

The Wikipedia article on this topic is very good. http://en.wikipedia.org/wiki/Electrocardiography#Waves_and_i...

If the heart is shocked (physically or electrically) during that recovery period, it can throw the heart into a fatal dysrhythmia where all the muscle cells in the heart are contracting chaotically. This is what happens when a baseball, lacrosse, or hockey player takes a blow to the chest and goes into sudden cardiac arrest... The blow happened during that very narrow window or time.

It's possible for your own heart to do that to itself though... It's very common for healthy people to have occasional 'premature ventricular contractions' where some random cell in the heart decides it's pissed off and wants to contract early. These are generally harmless, and happen all the time without anyone noticing. Every once in a while though, one of those PVCs occurs during that recharging phase, which can be very bad... So, a 'perfectly' healthy person _can_ throw a PVC, end up with an R-on-T contraction, and whamo... they're dead. Is it common? No, it's extremely rare. Does it happen? Sure does...

1 comments

I guess that depends on why you mean by 'perfect health.'

I know :)

He may very well have been in perfect health by every outward appearance.

Exactly what I'm saying.

There are a large number of surprisingly minor things that can make you dead in an instant.

Yes, but my contention is that the likelihood of these things happening is influenced by the degree to which your health is "perfect".

some random cell in the heart decides it's pissed off and wants to contract early

Again, from my point of view, the likelihood of this happening, or the potential harm that can come of it, is influenced by the level of perfection in one's health.

Your comment is very informative btw, so thank you.

I know we're talking about areas of health that are not yet very well understood, which is why there is scope for discussion, and why there are no irrefutable facts that can close the debate.

But this is exactly what I'm taling about; I'm hoping for a time when medical science has progressed to a point where these issues are very well understood, and seemingly random cardiac arrests like this can be preempted and prevented. I believe it's possible.

>But this is exactly what I'm taling about; I'm hoping for a time when medical science has progressed to a point where these issues are very well understood, and seemingly random cardiac arrests like this can be preempted and prevented. I believe it's possible.

This is simply a discussion of semantics, and I feel kind of silly for arguing it in the first place. You're absolutely correct that most of the 'random' sudden cardiac deaths that occur are in fact related to a previously unknown preexisting condition. Wolff-Parkinson-White, congenital long Q-T, and a variety of cardiomyopathies (most of them congenital as well) can easily predispose someone to dropping dead.

Wolf-Parkinson's, that's me. I was a highly-trained and mostly-healthy bike racer and would occasionally get a rapid, arythmic heart beat under certain conditions that would last for sometimes hours. Finally went in to get it checked, and when I asked "doesn't that result in sudden death in athletes?" He said if it hadn't killed me by now it probably wasn't going to. One heart ablation and it hasn't bothered me since.

My rambling point is that, yeah, "perfect health" sometimes isn't. And a few pieces of heart tissue that grew just a little differently could have meant I'm not writing this despite being a life long endurance athlete. I can't say it's changed my outlook on life much, though.

Did you feel anything during the ablation procedure?
Sorry for the late reply, I don't have reply notifications set up. During the ablation itself, I felt nothing because I was drugged. However, they have to repro the problem in order to know what to zap. That was an interesting process with all kinds of non-painful (though not entirely pleasant) stuff to feel. The details are still up if you care: http://psychocross.blogspot.com/2007/10/next-in-continuing-s...
Thank you.