SVT in 10 yr old

I have a 10 yr old who gets svt attacks every 35 days. This has happened now for the last 3 months.
Could this be some surge of some kind her body is giving off in what could turn out to be a 35 day cycle.
She has  now been put on atenonol 25mg and sees her specialist on 1st April but i am unsure whether my
theory would be laughed at or considered.

[Jeffrey R Boris, M.D.]

Dear Shell,

It is certainly not necessarily a strange theory, per se.  Your daughter has supraventricular tachycardia (SVT), which is an abnormal fast heart beat.  It is caused by the presence of an extra electrical connection between the top and the bottom of the heart, so that electricity can go down the normal connection and back up the extra connection very quickly.  If you daughter has started her menses, or at least has cyclical hormonal changes at this time that correlates to these, it may be potentially related.  There is much we don’t exactly know about the interrelationship between body hormones and the effects that they exert on the electrical conduction properties of the heart.  It very well may be that there is a relationship.  That said, it could be a circumstantial relationship.

At any rate, therapy for this can include medications, such as atenolol (a beta blocker), or other types of medications.  But, due to her age, the likelihood that this SVT will spontaneously go away is very low.  She is at a good age for consideration of electrophysiology study with radiofrequency ablation, which is a procedure in which a cardiac catheterization is performed in order to find the extra pathway and eliminate it permanently.  Depending on the location of the pathway, the success rate for this is quite high.