exercise induced sinus tachycardia

[worriedmom246]

My 13 year old daughter has been experiencing episodes of tachycardia since July of this year where her heart rate (with exertion) elevates up to 250 bpm. She is symptomatic....states her throat is constricting (feels like she cannot breathe), dizziness, nausea, can feel her heart beat in her head (pounding), and feels like she is going to pass out. his literally just started...one day she was fine and the next began having symptoms.  We have done an event monitor where several EP docs have said it is svt, however we just had a stress test done where there is a p wave.  We have tried beta blockers where she was hypotensive and had orthostatic issues so I was told by her physician to take her off of them.  I am at a total loss and don't know what else to do.  My daughter experiences these symptoms with any exercise that is more than a brisk walk and cannot participate in any of  the activities she used to.  I would love to find what causes this and get it treated so she can stop being so sedentary and have a normal healthy life again.

[is_something_wrong]

Hello,

I agree with the posts above. While I found the headline in your post really interesting (because I suspect my sinus tachy is high too sometimes when I'm anxious when exercising) I'm not completely convinced it's correct.

As Tom said, several supraventricular tachycardias can present with a P wave. At 250 BPM, this P wave can be impossible to differ from the previous T wave (atrias start to fire before the ventricles is done at that speed, this is normal).

I guess if you meant that during the stress test, heart rate climbed from resting heart rate to 250 BPM with increasing exercise level, then it may be sinus tachycardia (which is, by definition, a SVT anyway). If she gets sudden "jumps" in the heart rate, it's usually not.

I would show the rhythm strips from the stress test to your EP doc for a second opinion. Keep us updated on this one please, I think this subject is interesting.

[Bromley]

Wide QRS is sometimes difficult to differentiate. Both VT and PSVT can present as wide complex tachycardia.  One thing that can distinguish VT from PSVT is that the atrial component of the voltage trace can be disassociated from the ventricular component. The reason for this is that VT is like having the ventricles beating on their own, without involvement from the upper heart.  It might have been good news that the p wave was present, and in sync with the QRS.  Ask your doc.

[itdood]

Worried mom, can you scan in an EKG where she has this 250 hr?  Post it in your profile and give the Expert forum a try, there are docs monitoring that area.  Post it here as-well, perhaps someone may see something they recognize.

it sounds like several EPs made the SVT diagnosis, do you know what type of SVT it was?  SVT is a very broad term meaning the tach is coming from above the ventricles, in the atria.   It could be a reentry circuit, extra circuit, a-flutter, a-fib, sinus tach, I'm sure I'm missing a few.

[tom_h]

I'm confused a little.  Your title indicated sinus tachycardia, but in the body of your post, you say the EP says it's SVT.  Also, I don't understand what you mean by the presence of a p wave during her stress test?  A p wave is typical in the average heart unless there's afib present.  It can be elongated, raised, or supressed with other heart conditions.  On an EKG trace, right after the p wave is what's known as the PR segment. In this area you typyicall see a flat line.  But  sometimes you might see a slight slur or delta wave.  This is an indication of something called Wolff Parkinson White Syndrome.  This condition (as well as others) can cause sudden onset of rapid  heart rhythm. People with this condition are usually born with it, and it may lie dormant for many years and pop up one day suddenly.  This is known as an "accessory parthway"; a stray bundle of nerve fibers that conduct an accessory pulse which bypasses the normal electrical circuit in the heart.  This can be a nuisance when it crops up every now and then.  But if it's occuring anytime the an increase in physical activity, it might be time to do something about.

A few things you should know:
If it's SVT as the doc say it is, this is typically not dangerous if it's converted within a reasonable amount of time.

A long term monitor is available which can be worn for up to a month allowing the patient a better chance to capture the event.

With a lot of these types of SVT, ablation can be performed with great success.  This is done during an EP study.

Drugs help, but are not always effective in stopping it completely.  There are also things the patient can do when one starts up to promptly convert it and avoid going to the hospital

She is not alone with her condition.  There are a lot of us here that have had it for years and/or have finally free of it from an ablation procedure.  I had 54 years if SVT, and am one month post-ablation.

Plaease feel free to ask us anything you'd like.  I'm often full of crap, but I'd be glad to help as much as I can.  Mine started when I was 6, and I know what it's like to be a teenager and have this problem.