Atrial Fibrillation and the Athlete
Sunday, 25 April 2010
Have you ever raced and felt that you were about to explode? I mean really, really felt that way? Ever thought your heart rate monitor was on the blink, giving you spurious readings? Ever found it difficult to measure your own heart rate manually? Have you ever noticed your pulse miss a beat or behave erratically? Do you consider yourself as someone with a high level of fitness who has trained hard for years who is suffering a little dip in performance? Could be you are suffering from Atrial Fibrillation.
British Medical Journal
In a study published in the British Medical Journal it was noted that an intense athletic lifestyle usually led to better life expectancy than that of the average person (good news!), but at the same time, athletes are more likely to develop a certain, potentially life threatening, heart condition (bummer!).
The above article deals with orienteers, especially those who have trained to a high level for years, and how more of them (12%) suffer with this condition than ‘normal’ people (2%) . Unfortunately, it isn’t the simultaneous running around mountain sides whilst trying to read a map and use a compass that is to blame; it’s the same thing that regular competitive ski paddlers do all the time: training hard to go as fast as we can.
I had a major shock recently, regarding the state of my heart. I’ve trained pretty hard for most of my life, and ok, so I like a beer or two, but at the age of 43 I didn’t expect to be diagnosed with Atrial Fibrillation (where the electrical impulses within the heart get messed up).
Anyway, the reason I’m telling you this is not that I’m on the hunt for any sympathy (or a beer). Rather, I decided to do some research on my ailment and the results for people with a similar background to mine were quite, erm, sobering. It seems that there is a surprising numer of people in their 40’s who train hard and who actually have the same condition as me and don’t even know it. What’s more, it could possibly be the intensity of the training, especially when linked to other problems (e.g. hypertension/high blood pressure) that is pushing people, especially blokes, over the edge. Not only that, the older you get, the more chance you’re going to get it in the future.
With medication my condition has come under control, but it got me thinking. How many times have you heard of someone drowning on the sea unexpectedly and the reason being given as a heart-attack? What if the chances of this could be reduced or avoided?
The point of this article is to explain what Atrial Fibrillation is; who, potentially, is at risk; what the signs are; and what you can do about it if you tick the right (wrong!) boxes.
Before I continue, I should state that apart from my GB and Aussie Bronze lifesaving medallions, I have no formal education in any medical field. This is just a bit of amateur research that hopes to help some of you. With any luck it will kindle some more informed debate and perhaps we can all gain a better understanding of this problem – after all, that was my initial aim for myself in doing some reading around the topic- especially if much better qualified people out there read this and input their superior knowledge of the subject.
What is Atrial Fibrillation?
Wikipedia has a fantastic explanation, replete with moving diagrams to really put you in the picture:
And there is also a more in depth description with lots of discussion and useful information at:
Briefly, A-fib is a cardiac arrhythmia (abnormal heart beat). In layman’s terms, the electrical impulse that traverses the Atrium of the heart to fire a beat has been compromised. The electrical signals in the atrium are confused and as a result the heartbeat pattern can be very different from normal.
Normal Heart (J. Heuser via Wikipedia).
Atrial Fibrillation (J. Heuser via Wikipedia).
Sometimes Atrial Fibrillation, or A-fib, can be a stand alone ailment, but often it can be the result of hypertension (high blood pressure) or some other causes, such as alcohol abuse or possibly, intense athletic training. The BMJ article above noted the following:
‘Enhanced vagal tone, characteristic of endurance athletes, predisposes normal hearts to atrial fibrillation. Atrial enlargement and left ventricular hypertrophy, both features of the endurance athlete's heart, may further increase the tendency to atrial fibrillation’
Who is at risk of developing A-fib?
From the reading I’ve done, it seems that males over 40 years of age who train intensely are at a higher risk than the average person.
What are the signs?
For me, my top-end performance just seemed to disappear over the last two years. Easy to moderate stuff remained the same, but it felt like I suddenly had a regulator on my engine. If this rings any bells with anyone you know, on or off a ski, it could be a sign.
Racing in 2007 I was able to hold my own against other paddlers in my age-group and the Under-19s too. A year later I did a race in North Devon and I felt like I was about to pop. I was struggling to stay in the top-half of the field. All the guys I’d been competing head-to-head with the previous season were gone. I’d trained regularly all winter and yet there were numerous un-trained paddlers keeping up with me. Whenever I tried to up my effort, I could really feel the blood pressure inside me building up.
At the time, I figured I’d had a good few nights on the beer, and surely that was to blame. Give it a few days and I’ll be back to normal, I thought.
Training more recently involved preparing for the Dragon run in Hong Kong in November 2009. Here I realized that I could work on my stamina and successfully build up a long slow distance base, but the intense stuff was really making me suffer.
Crazy HRM Readings
After Christmas and a poor showing in Hong Kong, I decided to get a bit more scientific and go back to using a heart-rate monitor again. First off I was getting all kinds of crazy readings, even when at rest. Much as I thought there was something strange going on with my pulse, I had put that, and my lack of ability to complete intense training efforts, down to old age. It seemed a grudgingly correct assumption and perhaps a veil over the growing feeling that there was something seriously wrong - after all, I come from a background of macho surf lifesaving, like so many other paddlers, and I didn’t really want to make a fuss.
This February it dawned on me that I couldn’t even check my pulse manually. I used to do it all the time, especially in the days before we had HRMs, but now the rhythm of my heart would beat …/…../……../…………/.././././/……./……../…………../. I finally accepted that something was wrong and that I needed professional help.
With blood pressure measurements taken on each limb, ECGs, an ultrasound scan on my heart and a few chest x-rays, the doctor was able to confirm my A-fib condition.
The main problem with A-fib is how it can potentially multiply your chance of suffering a stroke eight fold. Due to the heart not pumping blood as efficiently as before, it’s possible that some blood can pool within the heart. Here it can clot and form a thrombus. Next stage it breaks free and travels along your arteries until the tube is small enough to block its passage, and if that artery is in the brain, then oxygen supply there is cut off and a stroke can be the result.
How is A-fib treated?
If spotted early enough, there are some processes aimed at correcting the irregular heartbeat, such as cardioversion (where a controlled electric shock is used to ‘re-align’ the electrical impulse system of your heart); or ablation (where micro surgery enables the surgeon to destroy any mis-firing parts of the atrium through removal or freezing).
Chances are, if you’ve had it for over a year and the condition has become chronic, then doctors are not usually keen to try cardioversion; and they tend to wait until recommending ablation. The other main solution at present is drugs, usually three different ones. One is needed to thin the blood to act against clots forming in the heart (think Warfarin or some such chemical); another is needed to try and regulate the beats of the heart so that they are not so random; and the other is a drug which is able to slow down the beat of the heart. The problem with drugs though is that they only hold off the A-fib temporarily, and that period could be enough to prevent you from having an ablation.
The seemingly good news where athletes are concerned is that doctors appear to be leaning towards ablation therapy before more damage is done to the heart. This information comes via A-fib.com, and here’s their report in full:
15th BOSTON A-FIB SYMPOSIUM, January 14-16, 2010 "Atrial Fibrillation: Mechanisms and New Directions in Therapy"
‘The annual international Boston A-Fib Symposium is one of the most important conferences on A-Fib in the world. It brings together researchers and doctors who share the latest information.
ATHLETES AND A-FIB
Athletes and endurance training was the subject of two sessions and a great deal of discussion. Dr. Stanley Nattel presented studies indicating that high level physical training doubled the risk of developing A-Fib. In Dr. Nattel's animal lab experiments, high level exercise training (30+ miles/week) developed A-Fib by two mechanisms:
1. increasing Vagal tone,
2. producing structural remodeling of the heart---atrial overload leads to atrial enlargement, increases atrial fibrosis and ventricular hypertrophy.
Dr. Riccardo Cappato described how A-Fib hurts athletes' performance and their ability to exercise. It also makes them ineligible for competitions because they fail pre-qualifying tests (other professions and avocations such as pilots have this same problem).
Because athletes often can not tolerate antiarrhythmic drugs and/or refuse to take them, Dr. Cappato and other doctors in a panel discussion say they recommend Pulmonary Vein Ablation as first line treatment for athletes. A successful PV ablation restores athletes to full competition intensity and makes them re-eligible to compete.
Current guidelines state "catheter ablation of A-Fib in general should not be considered as first line therapy." At least one antiarrhythmic med should be tried first. But the guidelines also state, "in rare clinical situations, it may be appropriate to perform catheter ablation of AF as first line therapy." Dr. Eric Prystowsky, who was instrumental in writing the current A-Fib guidelines, stated that he uses PV Ablation as first line therapy for athletes because of the above reasons.’
After a fortnight on the drugs my blood pressure dropped from 160+ over something, to 116/90. My resting heart rate went from something I couldn’t measure, to around 58 bpm with the drugs (fifteen or so years previously my resting HR had been 38 bpm).
In my case, it appears that the drugs are for life (that’s five whole tablets and two half tablets every morning with breakfast) unless I shelve out for surgery.
The biggest thing I’ve learned from my experiences is to really listen to all of the signals coming from the body and to confront them head on. I seriously advise anyone reading this to check their pulse… go on, do it now! Secondly, and especially if you are a male over 40, make sure the doctor gives you a full service check every year, and insist that you have an ECG at the very least. If the BMJ article is accurate, then 12% of fit older male ski paddlers probably are afflicted, whether they know it or not (compared to just 2% of the normal population – but hey, we’re expected to live longer!).
I’ll leave it there. Keen to hear what you think - especially with our sport catering to so many middle-aged men. But especially interested to see how many others are affected, even more so if this article plays any part in helping anyone find out, or even if it just makes us all aware of what to look out for in the future.
Here’s wishing you happy and continued healthy paddling (and at least I’ve got a good excuse now if I come last!)