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Date of last update: 10/20/2017.

Forum Name: Arrhythmias

Question: Palpitations during exercise

 KDCwv32 - Sat Mar 03, 2007 7:32 pm

Hi, I'm a 21 year old female in pretty good shape and lately the past 5 months Ive been having palpitations. I have never had them before so this is scary to me. I am a student so when i first started having them i went to the University hospital where they only did a resting EKG on me which was normal and the doctor said not to worry about it. I first starting noticing going up stairs. Now I only have them during exercise and its freaking me out! Sometimes it feels like my breath gets taken away for a split second and other times i just feel a skipped beat in my chest. The very first one I had, which was goin up steps, made me light headed but that was the only time. I don't drink caffine or any other stimulants. I drink alcohol but not very often maybe two weekends out of the month. My family has no history of heart problems once so ever. I have chronic costochondritis for about a year now and occasionaly protein shows up in my urine... i don't know if that has any link to it but just to let you know. I feel very nervous now when i start to run because of these skipped heart beats, so i usually try to avoid it but i love to run! Should I be worried? Do you recommend gettin more tests done?
 Dr. Chan Lowe - Sat Mar 03, 2007 7:48 pm

User avatar I would advise you to seek further evaluation for this. There are several things that may be going on. Often, the "missed beats" that people feel are early contractions of the ventricles known as premature ventricular contractions (PVC's). PVC's are generally normal and when the heart rate goes up, the PVC's go away. PVC's that increase with increasing heart rate are concerning and should be further evaluated.

There are a few tests that may be helpful for you. One is an EKG stress test. Basically they put you on a treadmill or stair stepper and monitor your heart rhythms. Also, a 24 hour holter monitor may be useful. This is basically an EKG machine that you wear for 24 hours to make a continuous recording of your heart rhythms. These tests can be helpful in assessing rhythm problems that occur during exercise.

You may need a referral to a cardiologist to have some of these tests done.

Keep us updated. Hope this helps.
 KDCwv32 - Sun Mar 04, 2007 8:22 pm

Thank you for your response. I have one other question should i discontinue working out until i have more tests done? I didnt mention that they don't occur everytime i work out just randomly.
 Dr. Chan Lowe - Sun Mar 04, 2007 11:38 pm

User avatar It is probably wise to limit your exercise some. I would not advise doing very strenous lifting or significant cardiovascular stressing exercises until you've been cleared by your doctor. It's probably safe to do low level exercise but if you start having symptoms I would recommend that you stop your exercise and rest.

Keep us updated.
 KDCwv32 - Tue Mar 13, 2007 4:00 pm

I'm getting a stress test done at the end of this month. I have another question for you. I havent had any skipped beats in a while so I went on a jog the other day. I didnt get any skipped beats but the right side of my chest felt like it was cramping so i quit jogging. This is a new symptom. I don't know if it's anything I should worry about since it was on the right side of my chest, but do you think that might be a symptom of something heart related?

Thanks again!
 John Kenyon, CNA - Tue Mar 20, 2007 3:25 pm

User avatar Hello KCDwv32 - While waiting for Dr. Lowe to add his thoughts in response to your most recent post I thought I'd throw in some of my own, as I have been unable to post for a couple weeks here due to strictly computer-related problems. At any rate, first of all, yes, I think that, as Dr. Lowe had already suggested, you might want to consider cutting back your fitness regimen, at least until the stress test has been completed. I suspect it will likely turn up nothing abnormal, although you may have some PVCs or PACs (Premature Atrial Contractions) show up during the test. Although it has long been believed that exercise-induced PVCs are a potential cause for concern, that mainly applies to people with known heart disease. It is fairly unlikely that you have heart disease, but you could possibly have a fairly common condition known as mitral valve prolapse (MVP) , which can cause a whole variety of benign arrhythmias including PVCs, PACs, atypical chest pain, intermittent fatigue (although exercise is usually well tolerated), and even anxiety.

The nature of PVCs and PACs is to come and go, and sometimes they can be linked to something (caffeine overuse, stress, etc.) but just as often the underlying cause remains an annoying mystery. They are almost never diagnostic of anything serious unless found in the presence of significant heart disease. You sound like you are a healthy and fit young woman (which makes it all the more difficult to slow down the usual fitness regimen, but bear with us here). Since your doctor has decided to do a stress test you may as well go along with the program and not test yourself by jogging or running until the stress test has been done. Brisk walking should be fine, however.

Oh, regarding that cramping in your right chest during jogging, that doesn't sound cardiac related, and probably is just a variation on the "stitch" some people get when running. However, once again, since you have a stress test coming up anyway, you may as well keep the exercise at a fairly low level until you know for certain that everything is fine. I'm betting it is, but medical issues aren't decided on a bet.

Please do keep us updated.
 KDCwv32 - Sat Mar 24, 2007 9:04 pm

Thanks for your response! Any advice is helpful. I forgot to mention this earlier which i should have but forgot. I had some blood work done a while back and my potassium level was slightly low at 3.4 is this low enough to mess with my heart? I've been eating plenty of foods that are good for K+ since then and it has occured less often but still happening. Thanks again!
 John Kenyon, CNA - Sun Mar 25, 2007 12:18 am

User avatar Hello again - Well to get straight to the point, yes! A lowered potassium level can definitely affect your heart. Now a lot of people would say 3.5 is the lower limit of normal and 3.4 is just a hair below that, but some labs now place the lower limit at 3.8, and many cardiologists will, when dealing with a patient with arrhythmic complaints want it to be at least 3.8 and preferably a little higher. Low K can cause palpitations, premature beats, various tacharrhythmias, etc. Also, some people seem to have a metabolic flaw that causes their serum potassium to be low much of the time, despite eating foods containing K. When this is seen consistently a doctor often may prescribe a slow-release potassium supplement. It's worth a try anyway, given the complaint and the lab results. If your heart were to settle down that would answer the question for sure.

Good luck with this and we will be waiting to hear how things turn out.
 Dr. Chan Lowe - Sun Mar 25, 2007 1:33 am

User avatar Sorry for the delay in responding. I missed your post a few weeks ago. I would completely agree with Mr. Kenyon's advice. Your potassium level is "borderline" low but when cardiac rhythms are in question, it is nice to have potassium levels closer to 4. Eating potassium rich foods or taking a multivitamin will likely solve this issue for you.

I would agree with the assessment of the right sided chest pain also.

Let us know how the stress test turns out.

Best wishes.
 KDCwv32 - Tue Apr 10, 2007 10:53 am

Ok so my Cardio apt got pushed back to May1st. But on another note. I went to the ER last Thursday. I was walking to class going up the hill and I realized that as I reached flat land and slowed down my heart rate didnt and I couldnt get it to stop. Then it started skipping. Luckily i was at the Hospital already for my class so I walked into the ER. They did blook work and said everything was normal except my K+ was low at 3.2 but that wouldn't have caused what they said was SVT's. They gave me a holter monitor for 24 hrs and it did skip while i wore it I just have to wait for the results. The ER doctor said not to worry about it and the nurse said it might have been an panic attack which could be true because I have been really nervous about this whole heart thing. Anyways what do you think of the situation? thanks for the replies!
 John Kenyon, CNA - Tue Apr 10, 2007 11:24 am

User avatar Hello - Well here's the deal: for some reason your body is not maintaining an adequate potassium (K) level. This happens in some individuals for reasons that can be figured out with a little detective work, but in some there's no readily apparent reason. This will cause a lot of symptoms including rapid heart rate, irregular beats and, yes, even SVT. K is essential to the proper functioning of the electrical systems in your body, especially your heart and those serving the large muscle groups. Loss of K can come from something as simple as a diet that doesn't include enough (some foods high in K are bananas, oranges, potatoes, avacados, dried apricots, etc. Adequate (but not excessive) fluid intake is also important. Getting dehydrated can lower K levels. People who take diuretics (fluid pills) have to take a potassium replacement, and some of us just need a medically supervised K supplement to maintain normal levels.

As I think I mentioned before, a K level of 3.2 is not considered extremely low, but most cardiologists will prefer it to be closer to 4.0 (3.5 - 3.8 is considered normal). Don't try over-the-counter potassium supplements,however, as too much is as big a problem as too little, and can be very dangerous. There is a relatively inexpensive generic form of controlled-release potassium available by prescription and can be very helpful in cases where there's no obvious explanation for the low levels.

Panic attack is another possibility, but as I gathered from your post and I know from observation and experience, panic attacks are caused by symptoms as often as they are the cause of symptoms, so while it's important to determine if panic attacks are a part of the overall picture, it's not something easily measured as by a laboratory test. On the other hand, potassium levels can readily be measured by blood testing, and you have had,on more than one occasion, a low K level accompanying these symptoms. Based on that alone I would say this is the likely underlying cause of the symptoms and the symptoms may have caused a panic attack, which would only make all the symptoms worse and longer lasting.

Interestingly, panic and anxiety cause increased production of adrenaline by our bodies, and adrenaline release can cause loss of K, so the two problems can be interrelated on more than one level. Still, it makes sense to go to the obvioius first, and in this case the obvious thing is that your K levels have been low on occasions when you've had these unpleasant symptoms, so it would seem reasonable to ask if your cardiologist might prescribe a slow-release potassium supplement for you. Make sure the cardio doctor knows about the ER visit, what led to it, and the low K level it turned up.

In the meantime try adding some potassium-rich foods to your diet (unless you're already doing that). And again, don't try the do-it-yourself approach to potassium replacement, as too much can be more dangerous than too little.

Good luck to you and please stay in touch. We'll be interested to know what your cardiologist has to say about all this.
 KDCwv32 - Tue May 29, 2007 3:34 pm

OK, so i got my stress done today and nothing happened... no skip beats and they also did an echo. I havent gotten all the results back but the doc said my echo looked fine and since nothing happened during the stress test im guessing im ok. Its so ironic that nothing happened but i guess thats good! Just thought I would update you guys and thank you for the advice!
 John Kenyon, CNA - Tue May 29, 2007 3:39 pm

User avatar Hi there! Well you'd be amazed how often people go in for a provocative test (like your stress test) and have absolutely no symptoms. It's especially true of PVCs, which come and go with no apparent rhyme or reason a lot of the time. The fact that the echo was negative is great (no structural heart disease and no flabby heart muscle), and the stress test was normal, and best of all, no symptoms! It is ironic, but it is also really good news. Thanks so much for sharing this with us. Hopefully this will have the desired effect of really easing your mind, even if the PVCs return from time to time.

Best of health to you and do stay in touch.
 Tinytears - Sat Dec 01, 2007 4:05 pm

I am a slim and healthy 45 year old woman. At present I am on a slow taper of Diazepam in order to come off sleep medication - currently down to 5mg per night, down from 10mg. Whenever I get hot or exercise I get random runs of ectopic heart beats every time. I have had an echo for mitral valve prolapse which was clear, my potassium level is 4.5, my thyroid and hb are normal and I don't have any stimulants. I had a stress test and my cardiologist said he wanted to make my heart rate so high that my normal sinus rhythm would "knock out" the ectopics. They started straight away and were very frequent (average 1 in 4) - I had to take my heart rate up to 180 before they stopped - I don't take it this high at the gym, and therefore have the ectopics for the whole time. My cardiologist wasn't sure if they were related to benzo. withdrawal or not and I have to go back in 6 months. I am scared of exertion now because I know what's coming - have you known this before, and was it a positive sign that even though it took almost to the end, the stress test did wipe them out even though it was at a high heart rate?
 John Kenyon, CNA - Sat Dec 01, 2007 4:40 pm

User avatar Hi Tinytears - Boy, I certainly can empathize with you on this one. The problem, such as it is (and it is a great one for a lot of people who are otherwise just fine, because of the intense anticipatory anxiety iit can cause), is a common one. While "overdriving" the ventricular ectopic pacemaker can work, there is also a paradoxical factor which often affects these beats. Some people have them mostly at rest and they go away with exertion, only to start up again when the exercise is over. Then there are others who get them when they start to exert, which is even more disturbing and frustratiog. The latter situation is more often seen in people with a high resting level of stimulants/irritants in their bloodstream,and so is often associated with benzo withdrawal. That doesn't mean that's definitely the cause in your case, but it certainly must be considered.

In some patients this pattern also just comes and goes, usually showing up during times of stress. Since benzo withdrawal can be associated with stress in a number of different ways, it does seem like a likely culprit in your case. At any rate, if you find this pattern lingers you will probably start to become less sensitive to it, but if you don't, don't feel bad. It is extremely unsettling to have this stuff start up whenever you try to exercise. Try to walk through it if you can, unless, of course, it makes you lightheaded, in which case you should advise your doctor. Apparently that doesn't happen or youw wouldn't have been able to push yourself past the overdrive threshold during the stress test.

It's scary stuff, but I think you've proven that in your case it is benign -- but that doesn't make it any less worrisome when it happens, which only releases more adrenaline and produces more premature beats.

It's crazymaking, but it really is benign. Good luck with this, and please do stay in touch.
 Tinytears - Sat Dec 01, 2007 5:30 pm

Thanks for your prompt reply John - it was very reassuring! I have read a lot about benzo. withdrawal so that I understand fully what I am doing, but although some people complain of palpitations, my heart rate can be quite slow but still throwing out ectopics. I understand that when in withdrawal, however controlled, the brain appears to be in a "hyper sensitive" state and therefore overreacts to things like adrenaline and noradrenaline. Does this stop when you eventually get off benzos. altogether? I can put up with this temporarily but not for ever! Many thanks.
 John Kenyon, CNA - Tue Dec 11, 2007 1:40 pm

User avatar Hi again Tinytears - Sorry to be so long in getting back to you with this reply, but I've been having some computer problems. Hopefully that's out of the way now.

You seem to be very well-read on the problems associated with benzo withdrawal and how the brain and descending associated systems react under these circumstances. As for your specific question regarding withdrawal-induced hypersensitivity and how long that might last, the answer is necessarily a little vague. While theoretically this should resolve fairly quickly once withdrawal is complete (and by now it may be), sometimes ectopy can be persistent once it has been awakened. This is often something that happens following an emotional stressful or physically traumatic event, and I would certainly call withdrawal from benzodiazepines something that could fall into one or both of those classifications. So, while it is likely the ectopic beats will diminish or disappear, chances are about even that they will not go away entirely, and may persist frequently for an indeterminate period. Once you're throught the withdrawal stage you should have a better idea about how this is likely to go. Eventually, in the absence of organic heart disease, they should go away or at least become intermitten (like most of us have them) once again.

The lack of feeling hypersensitive in itself should be such a relief that the accompanying symptoms, of which ectopic heartbeats are just one, should make everything seem a lot better, assuming there is no underlying anxiety problem which may still require medical management, as this can often be the sole cause of a hyper-alert central nervous system.

Oh, one other thing you mentioned was that your heart rate can be quite slow and still throw premature beats. This is actually a normal situation, although that may seem contradictory. Slowing of the heart rate and/or an overall slow rate involves stimulation of the vagus nerve, which is one of the primary causes of otherwise benign PVCs. I realize this doesn't seem fair, but it really is normal.

Hopefully by now things have already quieted down. Please do stay in touch and again, my apologies for taking so long to reply.
 Tinytears - Tue Dec 11, 2007 4:54 pm

Hi John - Many thanks again for your reply. I don't know if you know much about benzo. withdrawal, but it seems to get harder the lower the dose. I have been on 5mg Diazepam at night for 3 weeks and usually I have stabilized by now, but I am still getting the ectopics - really easily - I had a rich chocolate pudding last Thursday and that was enough to bring them on in 15 mins! , someone has suggested that it may be the tyrosine as well as the caffeine. Even if I just walk fast at the moment they start. I have never been so sensitive before, but I guess I've never been in this withdrawal position before either! It's going to take about another year to get off them at the rate that I am going (Ashton Manual) and it just seems like forever. Can you explain what's happening to me physiologically so that I understand? Hope I'm not being too technical! Many thanks indeed.
 John Kenyon, CNA - Tue Dec 11, 2007 5:41 pm

User avatar Hi there - No, you're not being too technical, and this sort of thing can be really scary and annoying. Diazepam, among the benzos, seems to be the one with the greatest withdrawal difficulty. Not impossible, but as you point out, often seemingly endless. It depends on the individual, but generally diazepam is harder to "disconnect" from than most of the others. That's in great part why it's fallen out of favor for long-term use.

What happens (and I'm sure you know this already) is that the effect of the drug blunts the body's reaction to normal stimuli. When it's withdrawn, the threshold is so much lower that everything seems to be hot-wired. It's a relativity problem, and the sensitivity takes varying times to adjust to normal while this is going on. For this reason it does seem to become more difficult as the dose gets lower, because at the point where you are now, you're stuck between a rock and a hard place for a while because you can't really just stop taking the medication, and yet each time you do, it causes something of a rebound effect in smaller and smaller increments, until you finally reach the point where it's really no longer "touching" the nerve center. At the same time you have to consider the body's innate ability to adjust after the blunting chemical is gone.

During this long, slow period of withdrawal, your body continues to be "teased" by the lower amounts of the drug and the rebound is more noticeable. To stop outright, as I'm sure you know, could result in anything from unbearably intense anxiety to grand mal seizures. You've definitely taken the less bumpy path. It's hard to realize that unless you've seen or experienced abrupt withdrawal from something similar.

Since the heart is such a great barometer of the emotional state in normal (non-drug-altered) situations, it is rather like a voltmeter run amok during this period. Very sensitive and irritable, much like the post-heart surgery patient. (The heart doesn't like being touched or handled either, and it takes a while for it to get over the insult, often with similar results). The continuous introduction/reduction of diazepam keeps the heart in this "cranky" mood til the whole process is over. It should become less so over time, but it is different for each individual.

I'm not sure I've made things any clearer, but I sure did use a lot of words! Hopefully this is some help to you. It will get better, and the upside/downside is that you will likely, at some point, develop a certain degree of tolerance for all the ectopy, at which point it will start to subside, because then your own emotional response and (natural) anticipation of the premature beats will then start to go away. As you've said, we can only stand so much of this. Luckily, there is a balance in things that makes our tolerance slowly go up over time, and this, in turn, shuts down part of the built-in "other drug", adrenaline, which is what is really the culprit.

It is, of coure, possible to try and counteract the overproduction of adrenaline during the benzo withdrawal by use of a beta blocking drug, but then you have the same situation all over again when you want to quit that -- although the beta blocker is far less of a problem in many ways than diazepam. You just can't stop either one of them cold. It is worth considering, though. Metaprolol or another beta blocker might be a short-term way to ease this particular symptom (the premature beats) during the benzo withdrawal. The beta blocker could then be withdrawn over a period of weeks instead of months.
Just a thought.
 Tinytears - Tue Dec 11, 2007 6:05 pm

Hi John - Blimey, that was a quick and thorough reply! I guess I sort of know all of this, but wanted to make sure that I wasn't kidding myself and hear it from someone else! My biggest fear is that after I withdraw, if the heart doesn't settle, I'll end up having a cardiac ablation which I really wouldn't want to do! Diazepam is the chosen benzo. for withdrawal because it has the longest half-life, which is meant to give you a smoother blood serum reduction - makes sense actually and is what Prof. Heather Ashton tells you to switch to - I was on a short life benzo. before and you practically get a mini-withdrawal every day on those because they come and go so quickly. Anyway, beta bockers would be a last resort for me because I'm trying not to depend on anything else but my determination, so wish me luck! Thank you so much for your time and I will keep you posted. I've got some liquid Diazepam for my next cut so I can make it smaller - think I cut too much last time and that's why I've suffered for longer than usual - slow and steady wins the race as they say! Regards.
 KDCwv32 - Thu Aug 14, 2008 9:31 pm

Ok, I have a question, I still have the occasional pvcs and pacs while running, I'm assuming that's what they are, but since they have never been caught on record anywhere what they are exactly should I be worried? I had a normal stress test and a normal echo along with normal holter monitor but while wearing all of these none of the episodes happened. Thanks!
 John Kenyon, CNA - Fri Aug 15, 2008 3:34 pm

User avatar Hi there -

As strange as it may seem, it is perfectly normal to have occasional premature beats (PACs, PVCs and even premature junctional beats -- PJCs) during exercise. While exercise can sometimes make them quiet down if they occur at rest, they can also occur during exercise because of the adrenaline factore. And since your echo and stress test were clean, there's really no need to be concerned, although I realize they can be pretty hard to ignore. Do your best, though.

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