Q+A: Why did my heart rate shoot up 40 beats?
Our experts answer real-life questions
Posted: 9 September 2002
by Gregory Whyte
Q During a recent race, while I was running very comfortably, my heart rate suddenly shot up to nearly 40 beats above my usual level and remained there for the rest of the run. At no time did I feel ill or even out of breath, but understandably I was worried. Ive since seen my GP and am waiting to see a cardiologist, but can you offer an explanation?
A Assuming that your heart rate monitor was not temporarily malfunctioning, and while its difficult to comment upon an individual case, I will try to offer an explanation of the commonest cause of unusual heart-rate fluctuations experienced by athletes. Heart palpitations are common in athletes and are usually felt as a regular pounding or racing of the heart in the chest, throat, and/or neck. Some athletes describe it as the heart stopping and then restarting, or a rapid fluttering. Many of the causes are innocent but some do require further specialist investigations.
The heart normally beats in a regular (sinus) rhythm with the upper chambers (atrium) contracting first, followed by the lower chambers (ventricles). The contraction of the heart is facilitated by an intricate wiring system that can be examined using an electrocardiogram. Palpitations usually result from a premature contraction of the heart muscle, which causes the symptoms mentioned above. These premature contractions are normally short-lived and the heart quickly returns to its normal rhythm.
The low resting heart rate of many runners may be one of the causes of palpitations. Others include stress, caffeine, alcohol and certain drugs (including some cold cures). Many athletes will experience palpitations, which usually only last a couple of seconds, during their athletic career. Indeed, everyone will experience palpitations at some time in their lives, and the palpitations brought on by strenuous exercise or high emotions are rarely associated with underlying cardiovascular disease.
However if palpitations are a frequent occurrence or continue for many minutes, and/or there are other associated symptoms (such as unusual shortness of breath and sweating, dizziness or fainting) you should consult your doctor. This is especially important if you have a family history of heart disease.
Dr Gregory Whyte, research manager, British Olympic Medical Centre, Northwick Park Hospital, Harrow
Discuss this article
The recent letter about erratic pulse measurements (RW, May 04) seems related to this thread, and certainly struck a chord with me. I too have often noticed erratic readings, and had put it down to interference from pylons, railway lines, electric gates etc. Except that it was happening at other times too - on the beach, in the woods - when there was no obvious source of interference. Then I started noticing my pulse speeding up when I wasn't exercising. I strapped my monitor on, and my pulse would be way over 100, when I wasn't doing anything, and would expect it to be 50-60. My pulse would be erratic, shooting up, and dropping down, but generally higher than normal. These 'episodes' would occur fairly infrequently (every few months or so), for no apparent reason, and would last a few minutes, or a couple of hours, then subside, leaving my pulse to gradually return to normal. Recently, they have been getting more frequent (2 or 3 times a week), and lasting for longer (up to 15 to 18 hours), including overnight. There is no pattern: I have stopped coffee; they occur at any time of day, though often late evening; regardless of exercise, alcohol, or food. In short, there is no discernable pattern. My GP referred me for a 24-hour ECG which was inconclusive, but the consultant has said it is probably 'paroximal (?) atrial fibrillation', which in itself is harmless, but I need to undergo more tests to see if there is an underlying reason which causes the condition, and could explain the increasing frequency. I am a 48-year old male, 5'10", weighing 11st, running regularly for 20 years. I don't smoke, and drink in moderation. My normal resting pulse is about 44.
Is this condition common amongst runners? Is there a common underlying reason? Are there any things to do, or to avoid, to stop it becoming even more frequent?
Posted: 28/04/2004 at 10:57
Lindsay, I have cut and pasted my reply from my friend Derek. I hope it helps.
With regard to your friend I would suggest she tries to get in touch with a cardiologist specialising in sports related problems.These usually based at big hospitals, possibly Guildford, St Georges Tooting & I think now, Mayday. However she could try the British Olympic Test Centre @ Harrow Hospital where I was sorted. Talk to Greg Whyte 020 8640609. Be aware their policy has changed due to funding & he may not be able to help. Normally they would put her on exercise test to determine the problem or possibly do an angiogram, the camera in the groin job to check the arteries. If she uses HR monitor it may be worth keeping record of when instances occur, weather conditions, type of training, does food affect it, what no HR goes to etc. There are obviously loads of causes for this problem, mine is electrical. Just as an aside my tablets are FLECAINIDE ACETATE. If she wants to have a chat get her to give me a call.
I can let you have his telephone number if you want to have a chat with him, his name is Derek. He has put the Guildford contact because I live in Guildord and he is presuming that you do too!
Posted: 20/04/2005 at 08:41
Following my post of 12 months ago, an update: after further tests, including echo-cardiogram and several 24-hour ECG's (which never co-incided with an 'epidode') I was put on beta-blockers, to slow my heart down, but these were useless, as all they did was just that - slowed it down. This meant my resting HR came down from a healthy 44 to below 35, and I my max dropped to around 140 - it meant even an easy run felt hard work. Also, they did little to stop the fibrillations occurring - they were just a bit slower. Eventually, I was put on Flecainide Acetate, and these seem to have done the trick - my heart is more regular, but within the normal range, meaning I can run, do intervals and even race. I still get the occasional 'attack' (my consultant called it 'paroxyssmal atrial fibrillation' - I guess that's the same as tachycardia), but not quite so often, and definitely not as severe, or long-lasting. They still occur predominantly in the evening, often just on going to bed, so maybe low hydration has something to do with it, but I've also noticed another trigger which if it wasn't so consistent, I'd dismiss as bizarre :- if I do anything which involves bending and twisting, this can trigger it. Bending to lift a heavy weight can do it, but even bending to get something out of a low cupboard, or twisting sideways can cause it. My theory: pressure near the kidneys, where the adrenal gland is situated, causes a fluctuation in adrenalin, triggering a fluctuation in the heart-rate. Doesn't explain why it doesn't come straight back to normal, but I did say it was bizarre
Posted: 24/04/2005 at 21:57
On the subject of the drugs available, Flecainide Acetate included (thank you, 'Ceal'), the curious thing is that side-effects include the very problems the drugs are prescribed for, palpitations, arrhythmias, even heart failure. GPs and cardiologists seem to like them. There is a surprisingly large number of them. One of our GPs in Castle Donington suggested I choose one at random and try it. Perhaps they work by making the heart so wrong it might just become right. The drugs don’t address the root cause of the problem, they merely slug the heart which means they can never be satisfactory for active people, and worse, there is the addictive effect, in that there are serious withdrawal symptoms and risks. Once you start taking one of these powerful drugs, the heart adjusts to it, and you can not easily go back. Catheter Ablation can be a complete fix because it burns out the rogue cells but does have serious risks like damaging or burning out the wrong bits (equals pacemaker required or sudden death). All that said, it is encouraging to hear of two semi-success stories with Flecainide Acetate but I won’t be trying it just yet, still too scared of a repetition of my experience last year. A cardiologist persuaded me to try bisoprolol, a beta blocker (brand name Cardicor) with the specific promise of carefree running again. Reluctantly I agreed a month’s trial. After 7 days the tachycardia bursts had become slow and damped but more frequent and same intensity and the chest felt filled with cement so there was clearly no fix happening. More serious, there were new symptoms, dizziness and nausea during tachycardia episodes. Also I began feeling generally unwell and disconnected from the world. For all these reasons, I stopped with just 7 tablets taken. That’s when the drug really hit me. Withdrawal lasted three months. The chest felt bruised and tender, the solar plexus constantly jittery. The first few weeks I experienced extreme exercise intolerance, like having to shower sitting down, take rests while brushing teeth, walk at a snail’s pace, otherwise the heart would race (in normal sinus mode).
Posted: 04/05/2005 at 15:02
Lindsay, sorry to hear about your bad experiences with BB's. I took Sotalol for about 3 months, with the effects described previously. Initially 2 per day, but that slowed me right down. Reducing to 1 per day meant it had no effect, so compromised at 1.5 per day. Pulse reduced, fibrillations reduced, but everything else reduced as well! Not quite depression, but getting that way. Been on Flecainide for 9 months with no problems so far. Had come to terms with long-term (i.e. permanent) nature of medication, but hadn't realised the 'addictive' effect. Will speak to GP at next review. Looks like everyone's condition and/or trigger is slightly different. In my case bending/twisting (thanks for confirmation by the way - I thought I was imagining it) is just one of several causes. Exercise does NOT seem to be a trigger, as episodes occur independently. I sometimes get them just after exercise, very occasionally during (once during a race), but usually not connected. Over a 10 week period last summer, I had 25 episodes at different times of day (mostly late evening) varying in duration from 30 mins to 30 hours, with average 12 hours. Only common thread was after effects: faintness on getting up, and extreme fatigue as though I'd been doing strenuous exercise for the duration. Needless to say, if they occurred during a race, or the night before a race, my performance suffered. As my condition is 'paroxyssmal' (i.e. intermittent), and rights itself eventually, ablation was not an option. Apart from which, I'm not THAT P.M. !!! Regards, PM
Posted: 06/05/2005 at 09:27
|
 |
| Free, fully-personalized training plans, designed to suit your racing goals and your lifestyle. |
|
-
22/05/2012 22:58:37
16 comments
-
22/05/2012 22:57:38
205290 comments
-
22/05/2012 22:57:22
5 comments
-
22/05/2012 22:56:48
8 comments
-
22/05/2012 22:55:14
9785 comments
|