Fast and Slow Heart Rate

[Neener44]

First of all thanks so much for this wonderful forum and the great service that you provide. I have learned so much from reading the information posted here.

I am a 48 year old female in good health. I've had two EP studies and ablations to correct what my doctor originally thought was a form of SVT, but now says is probably IST or sinus node dysfunction. After both procedures the fast heart rate returned and I was prescribed sotalol to help control the problem. (Other drugs have been tried, but did not work for me)

Since June I have been very dilligent in my exercise regimin which includes walking/jogging 6 days per week and weight lifting 2 days per week. I wear a polar heart rate monitor while exercising and have done so for the past 3 years. For the past 3 months I have been getting some weird readings and symptoms. When walking/jogging on my treadmill my heart rate starts out slow, usually in the 60's and then after a few minutes will jump to the 120's to 130's and then as soon as I begin to jog it jumps over 200 and then generally stays at 190 or higher for the remainder of my workout. I've had the monitor checked by polar and they said it was working correctly. I've also had my husband and son use my monitor and it works fine for them.

Finally, I have also noticed that my heart rate is very slow at times when I am just sitting. One evening while reading I started feeling dizzy and checked my pulse and it was 34 bpm. My resting heart rate has been in the 90's for years so this is weird for me. What do you think is going on?

[tpmjaney]

I too would like to submit tahnks for the great forum.
In my case this particular issue is one that really makes me feel I am not alone.
My problem is similar to neener99.
I've been a runner for close to 30 years.  During that time I often used a heart rate monitor while running on a treadmill. Most times the heart rate was what I considred normal.  However, occasionally the monitor went haywire (heart rates varying from low to a high of 180).  At the same time I felt an irregular heart beat.
Eventually the irrefular heart beat became the norm.....so I went to a cardiologist.  After a period of 2 months on medication the doctor decided I should be cardioverted.
The cardionversion was succesful.  At least as far as the EKG indicated.
However, when I ran on the treadmill, with the polar heartrate monitor, my heart rate started out over 200.  This usually lasted for 3-5 minutes and then the heart rate would return to around 130-140 (this for a 7:30 pace)
My doctor said it is the monitor not my heart and that I should take my pulse manually.  I tried that but as soon as I quit running the monitor and the manual pulse revert to what I consider a normal pulse.
Based on previous forum comments I now believe I will once again pursue this matter with my doctor.  Thanks for the info.
I

[wingtip]

For what its worth,  I use a cardiosport monitor, and found that I was getting the same types of readings you were.  I tried a polor monitor and found it to not be a sporadic in its readings, but still would climb over the 200 mark.    My monitor company said it might be in the programming of the monitor and the way it takes its readings.

The holtor monito proved out the fast rate, but because I am in cronic a-fib, it doesn't seem to concern the docs.  I still think the doctor is correct when he states that monitors are not programmed to handle any abnomalities in the heart rythem

[Neener44]

Thanks again for your comments. I've been experiencing this problem for about the past 3 months. At first I thought maybe I was just picking up electrical interference so I tried jogging outside and my heart rate still jumped up over 200. I've also tried gels, water, spit, etc. to make sure the electrodes have a good contact and I still got the same readings. I've also manually taken my pulse and it is either really fast or irregular. I've used a heart rate monitor for about the last 3 years and never had this problem before so I think something must be going on. My dose of sotalol is now the lowest possible dose. I've been taking sotalol (betapace) for over 4 years and the 40 mg dose doesn't really lower my heart rate very much. Hopefully, my doctor will figure out what's going on. I'm starting to feel kind of crummy like I used to when this all started over four years ago. I keep feeling like I'm going to faint. No fun.

[WPWGuy]

I agree. 48 seems too young to be having that kind of problem.  Hopefully, the slow rate, and dificulty getting over 65bpm can be explained by too high a dose of beta blocker.  I suppose it is conceivable that the dose might have gotten too high as a result of a misconception you or your doctor had as a result of what your polar was telling you.

To Mantel's point, perhaps an inadequate connection, or as Dr. BKJ has suggested, an effect of PVC's on measurement. Perhaps even noise induced from your treadmill or other electromagnetic sources could throw that puppy off. Something like that would not be unheard of at all.

Later...

[Neener44]

Hi
Thanks for your comments. I spoke to my EP's office and they are going to do a holter monitor initially and have me just do my regular routine at home. Hopefully that will pick it up. I do occasionally have a "good" day when my heart rate doesn't go over 160 or so. I've been researching on the internet and wonder if I am starting to develop sick sinus syndrome. Some days it takes 5 or more minutes to get my heart rate above 65 other days the minute I step on the treadmill it jumps to 190. I really don't want a pacemaker yet if I can avoid it.

[Mantels]

I have a Polar heart monitor as well. At 43 I had an MI I had a 100% blockage of LAD and 2 stents. I started running 3 months post and have lived with my monitor. I am taking ToprolXL which keeps it low. The problem I found with the Polar is if you do not have enough sweat the monitor will jump to 215 or so. Polar has told me that it will be artificially high until there is enough liquid (sweat,spit or believe it or not KY warming liquid) to get a good reading. I have more problems in winter than summer.

Hope this helps.

[WPWGuy]

On the other hand, if you did the holter, you could run the holter when you know the polar is giving you 200 bpm. In the lab, they might be signal averaging, and I imagine you wouldn't be wearing your polar.  Come to think of it, Im not really sure which would be better...

[WPWGuy]

I think that you should follow through on this advice.  If u could do only one of these things, maybe you would like the idea of doing the stress ecg the best, even if it costs a little more, and especially if your 200 bpm is consistantly repeatble everytime you exercise.  That way you get 12 leads worth of information (6 times as much) for the same effort.

If so, you could also ask about the willingness of the lab to adjust the test appropriately for your level of fitness. That might mean doing your normal routine on the treadmill in the lab, instead of doing the regimine they give everybody.

Good luck.

[Neener44]

I forgot to add that my dosage of sotalol has been reduced to 40mg every 12 hours. Also, I have chest pain or tightness in chest when I exercise, also dizzy and short of breath at timea, but I had an angiogram Fall 2003 and arteries were clear. The doctor prescibed prevacid which I took for about 2 months, but symptoms did not change. I quit exercising for about 2 months, but started again in spring of 2004.

[Cleveland Clinic]

neener,

thanks for the post.

A heart rate monitor, no matter how good is really only effective in people that have a regular rhythm. People that have PVCs, PACs, afib or other heart rhythms often find the same problem you are having.

What might be helpful is to do a stress ecg or wear a holter monitor and see what your actual rhythm is doing during this time. It might be as simple as a few PVCs but given your symptoms with a low heart rate it is important to confirm your underlying rhythm.

good luck