Exercise-induced Bradycardia

[Nickygg]

Hi,

I am a 31 year old female with a VERY long list of medical problems, and I have recently stumbled upon something else that concerns me...

Two days in a row, on different treadmills and once with a heart rate monitor, I have seen that about 15 minutes into a run my heart rate has gone from a 200+ down to a 30-50. Today, which is when I added the monitor, it showed that I stayed at a 30 for almost a minute, then went to a 0 for a couple of seconds, and then slowly climbed back up to a 40, 41, 50... then it spiked again at a 200. After my run, as I was cooling down (which I obviously stopped running right away), I remained at a 187-193 until turning the treadmill off. Even while stretching I found I stayed at a 180, and at one point I dropped to a 106 then back to a 180-something again...

So I'm obviously disturbed. So I don't know if anyone knows, but here is my *relevant* history...  I had brain surgery for a chiari 1 malformation/syringomyelia (C4-T10) exactly one year ago, I have a history of melanoma (and have had a lump in my neck for a year now--- which is being biopsied at the end of the month), I have type-1 diabetes (which I've had for almost 4 years-- 2 years of which my a1c was above a 15), I currently have a staph infection (I think... no lab work, but my GP believes that's what it is), and I do have high cholesterol...

I did see this last year, which was the last time I checked my heart rate during exercise, right before the brain surgery. My doctor at the time explained it was because of the CM1 and syrinx, which was affecting my blood pressure (because it was on the cerebellum)... I haven't checked my heart rate since because my blood pressure did drop dramatically after the surgery, enabling me to come off the medication, and I thought it was solved...

So help me. Please. I have had so many conditions that I don't know what is what, and I do not know which symptoms are relevant to anything... If anyone has any ideas, I would be very grateful for some feedback...

Thank you for listening!

Nicole

[Ashlee108]

It's very interesting you are having these problems I'm 29 years old and was diagnosed with chiari one malformation about 2 years ago after suffering with a head ache that felt like a stroke. In the past year I have began to
Go back to the gym and I am having the same issues. I typically only get my heart rate up to 160-170s and it drops into the 50s. At first I thought it was a bad reading but I have checked it manuelly with a heart monitor and a person trainer. I have seen a cardiologist with no explaining ether. I also have an unspecific connective tissue disorder so they thought that may be related just still unsure. Over time tho each time it feels worse I had an episode last night that actually made me go instantly pale and exhausted to the point I had to push through the last 10 mins of my exercise at a very slow pace. Just be careful and keep pushing your doctors maybe one day we'll figure it out maybe related to chiari. Hope this helps

[is_something_wrong]

Something seems very weird here.

If you exercise at max heart rate (200), a sudden drop to 30 with a duration over a minute, would by near 100% certainty make you faint.

A heart rate of 30 is not sufficient to do anything. Some people (usually those amazingly fit) get rates that low, but only during deep sleep, where our body functions works at a minimum level.

I have no good answer to what this is. With a heart rate of 200+ it's a possibility you have an arrhythmia (or extreme anxiety). You need a Holter monitor to wear during exercise, as you need a complete EKG (the pulse measuring is not good enough itself). That's the only way to tell what this is and isn't.

I really doubt your heart rate is this low, but certain conditions (such as A-fib) can make some of the heart beats (or most of them, it depends) unreadable to pulse monitors, because the pulse wave is so small due to the high heart rate. Another possibility is that your high heart rate is mixed with PACs. In that case, the pulse monitor only picks up the beats after PACs if your heart rate is really high.

You need a Holter monitor to find out. And there is, of course, a possibility the pulse monitors are inaccurate. It happens a lot. Especially with really high heart rates.

[cindy707]

Okay i'll throw in my two cents worth here...it definately sounds like you are on some faulty equipment/treadmill.  You have to remember that if its the type of treadmill that catches your heart rate thru the grips that you hold onto it is very very inaccurate especially at a gym or at home.  If you lessen the pressure it has a direct effect on the reading as well as if you use too much pressure.  Almost any equipment used for rating of the heart and blood pressure has to be calibrated on a regular basis for accuracy...there are so many questions here...my bet is on the equipment and i think that gatewaycat and Pamz are right on the money w. this one....you could always ask your doc to put you on a holter monitor for a week or so to get an accurate idea of what is really going on...good luck Nicky.....

[Pamz]

I'm sorry you've been dealing with so much.  I certainly hope it gets better for you from hear on.  

I've been dealing with personal heart rate monitor's this last week that had readings all over the place and had one on when the doctor was reading my pacemaker/defibrillator.  I thought my old one was accurate because it showed a rate that I was shocked at by my defibrillator but it turns out that the battery was low and it was showing really high and low readings, including some zeroes.  So, I bought a new one that picked up interference and was extremely high (over 200).  My doctor allowed me to test my old one while they were reading my device.  The hrm was slow and we determined that it was way off if it was too dry or not getting a good connection.  

So, make sure that everything is working correctly and, to be absolutely certain, get a doctor to monitor you.  

Hope you feel better soon!    

[gatewaycat]

Are these readings done using medical equipment (several electrodes) during a stress test or stress echocardiogram?

Consumer heart rate monitors can miss beats and give the wrong reading. The reading will drop suddenly on my when I exercise all the time, and I know the reading is obviously wrong.

If your heart can sustain running while at 30 bpm, then your heart is amazingly fit.