What Causes my Heart Rhythm Disorder?

I’m a Prof in medicine in the University of Washington and my Ph.D. is in epidemiology, but what I’m going to talk about today is out of my clinical area and it’s my story about my heart rhythm disorder.

The story starts I just graduated from high school. I was playing tennis and I had a sudden onset of this rapid and uncontrollable heartbeat. My heartbeat went from 100 to about 225, and that lasted for about five minutes and you know understandably I was pretty concerned.

I went to a stern looking physician and he says you have paroxysmal atrial tachycardia! You must stop drinking Coke right away. This may get worse and you may need to take medications and that was it.

Then over the next essentially 15 to 20 years, I raced bicycles, triathlons and these events would happen but I got used to them. They’re still a little scary, but they happen to or three times a month and I knew they would stop after a few minutes.

Then I got married, started a family, stop cycling, gained £35 and my heart rhythm problem was the same thankfully, but I developed high blood pressure. So my cardiologist who is really outstanding, he gave me six months and he said you have got to start taking medications now. I was 145/100 and 510, which is pretty high blood pressure and I said give me six months. I’m going to start cycling again and I don’t want to take medications yet.

So then I tracked myself and this was the first thing I tracked, and I lost a pound a week. And these embarrassing photos, the black one is because I didn’t actually have the nerve of taking a picture of myself when I weighed 205 pounds. You can see my daughter is in the middle picture watching me, but then I was able to lose 35 pounds over an eight-month period.

This was how I did it.

I began cycling a few days later. I changed my diet usually one item at a time. I weighed myself every day, which at the time it was strongly advised against and now the science shows that valuable.

I signed up for a long distance cycling event on a tandem called RAMROD, which is 155 mile ride, and I made this is a lifelong commitment to help my lifestyle at that time in 2000 that I have kept to this day.

So one of my big goals then was my brother is on the back of this tandem and I’m on the front, and you can see this profile of this ride and it has two mountain passes and 10,000 feet of climbing. So the impetus is to lose the weight because I couldn’t weigh 205 pound I had to be light, because not only did I have to be a strong cyclist I had to be light enough to go over these mountains and also not to slow down my brother who was counting on me. So it worked well for me.

But then at a research meeting in 2002, just about a year later for the first time in my life I thought I was going to die. I was back at a conference room just like over here, and I had already given a talk the day before but I have this feeling that my heart had stopped for about five seconds, and then I had this terrible irregular beat and then I thought well maybe this is what de-fib or v-tac is like and I started greying out.

And I really thought I was going to die, and instead of raising my hand, and you might think you would try to call for someone to help you, it was exactly the opposite. And I just sort of slumped down and thought my family and I thought that was it.

As it turned out I was able and really lucky and I thought I would have to go to the emergency room and it would stop after five minutes, and one of my colleagues and she had the story and she said Mark, I think you have atrial fibrillation and you’re probably okay, and you should go to see your cardiologist as soon as you get back tomorrow to Seattle and so that’s what I did then.

So, some of the background, some of the tachycardias the heart rate beats at 100 per minute parosxymal supraventricular tachycardia which I have is relatively benign. Something called atrial flutter which is relatively benign. Atrial fibrillation which can cause stroke and heart failure and can be very dangerous. And then there’s many things but just to name one there’s Wolf Parkinson White syndrome which can cause sudden cardiac death. So part of the cardiologist then if they are trying to rule out really dangerous disorders from the ones that aren’t dangerous.

So, I went into see my cardiologist and he asked me a million questions, and at that point I realised even though this was a monitor here that was placed on me and I had to do this several times, and they are able to record some of the ECG which is really powerful. Still the history is important in cardiology, and I didn’t have a lot of the answers to the questions that my cardiologist just asked me.

So at one point I really decided that I need to pay attention to all of this information and to start describing events, measuring these triggers and avoiding them to see if I could decrease these unpleasant and dangerous events.

And I would get this terrible choking feeling with this atrial fibrillation and it really felt like somebody was strangling me.

So really simple, I just started keeping track of the number of episodes and how long they lasted, the heart rate onset and offset, the time of day etc. and I started seeing some patterns then that I had actually maybe up to 3 different kind of arrhythmia.

So the first kind of thing I did then was to try to categorize the kind of arrhythmia, and the one that was very dramatic was like I had had in San Diego in 2002 was the terrible choking feeling, the irregular heartbeat, completely irregular. I had this sense of an impending doom, and I had very lightheaded and I had a feeling that one was coming on, a prodrome. And sometimes I would get up to 5 minutes and feeling it was going to happen before it would happen, and they would last anywhere from two minutes all the way up to 30 minutes.

And then I had this other one that was rapid and regular like I have had since playing tennis when I was aged 18 and it really wasn’t that bad. Then there was one that was a little bit in between these two.

So what I did then was very simple. I just created an Excel table with all the episodes, the date, time, length, where and prognosis between these three groups. Onset and offset symptoms, and also my estimated heart rate. Some of them I was able to record with heart rate monitors, and then I looked at triggers.

So by doing that I was over four years, and this last year than that I have depicted here in purple are the atrial fibrillation episodes are 0 to 1 luckily and not to many but they are very bothersome. And then also the supraventricular tachycardia which looks like it has some seasonality. And then I actually did a trial with magnesium to see if it could decrease it, and it did decrease here but I was a little bit skeptical about whether it was really due to the magnesium, because when I decreased it later the actual rate went up again. So it didn’t have an effect on atrial fibrillation, but the ACT did go down and there was all different kind of factors and there wasn’t any kind of control.

So what about the triggers, and that was the thing that really became interesting and could I quantify those triggers and could I use any epidemiological method from etiologic research like in cancer to answer the question from myself.

And there is something called from Mittleman and McClure a couple of epidemiologists which is a case crossover design and that’s the way to ask and answer the question, what are you doing right before you have the onset of the disease and is there anything unusual at all.

So in this kind of design it’s really not that well known. You need to do a comparison within the individual. So I knew it would be perfect for me because in this way I could compare what I was doing right before having an event with what I usually do. And so you can actually have two comparisons. You can have one which are on days when there are no events and one when you have the events.

And so you have a hazard and control period, and then by doing this you can then go ahead and use something called the odds ratio, and create a 2 by estimates of any kind of 2 table 2 actually, with quantified estimate with any kind of precipitation.

So I went ahead and did that then for one year, and I found some interesting findings. And one of them was high intensity exercise had an odds ratio which was four times greater risk learn if I had that in the hour before then if I didn’t.

I also found something interesting and associated with caffeine, which is 50 mg or more after 2 PM would really trigger these. The public meeting in large groups I also found, and there are a lot of factors which are related to that which is usually not getting enough sleep, and stress but actually seem like a big risk factor, and inadequate sleep in the previous 12 hours so less than six hours sleep.

The atrial fibrillation factors were very similar but caffeine it didn’t matter at what time of day it was, and usually air turbulence was a risk factor for me, so it always kind of bothers me and that’s our rarer event so a bigger odd ratio. And again I found this association with drinking wine, and public speaking and large groups. And also inadequate sleep.

I don’t feel like I’m going to have one now, but I thought that would be bad form if I collapsed here right on the stage today.

So the take-home message was that I use this information to minimize the precipitants and I was able to decrease the number of both types of episodes. And I ended up having three cardiologists that I work with, and they were very good about listening to what was going on, and being able to tailor the kind of procedure that I ended up having and I was really thankful for that. And I think it helped that I had the information and then I ended up having a far less invasive procedure and just had a very easy ablation procedure for one of my arrhythmias, and then it knocked out all three of them.

And so my cardiologist said when I came back a month later he said, well this is a home run Mark and this is like the best possible scenario that we are able to ablate which was a real flutter that I had and I now no longer get the other arrhythmias.

So I would like to summarize this by saying that self-tracking it help me identify a precipitating factors in a life-threatening heart condition. And I think single subject design as used by the Quantified Self proponents deserve far more study and valid publication, and single subject designs truly have a place in science and evidence-based medicine there’s methods available that can be expanded.

So with that I would just like to thank you and your kind attention.