SVT

[valjean1]

My son has had 2 ablations last year due to a left accessory concealed pathway of SVT.
He was still feeling symptoms of heart racing and then the EP recommended an EP study to try
to stimulate the SVT and then we were going to try stronger medicines since the others medicines were not
working.  The EP could not stimulate the SVT during the EP study.  He is still having symptoms of heart racing.
Can the SVT still be there even though you could not stimulate it in the EP study?  
Thank you!!
JT

[vsthom]

Thank you.  If his episodes continue we are going to get a monitor.  He has had his SVT caught on these monitors in the past last year but not since the 2nd ablations.  His SVT was very close to the coronary artery.  Is this more likely to reoccur in this location?  The doctor only used one catheter in the EP study instead of 3 in the ablation.  Does the number of catheters affect the strength or ability to stimulate the SVT?  thank you!

[Marie M Gleason, M.D.]

When someone experiences "palpitations" it means they either feel their heart beating faster than normal, or irregularly.  Although it is possible for SVT to be recurrent, that is only the minority of cases after a successful ablation.  If the mechanism of the SVT was a concealed pathway, and that pathway was not fully ablated, then they SHOULD have been able to reproduce the SVT in the EP lab.  It seems that documentation of the heart rate that your son is feeling is needed.  That can be done with event monitoring that is worn continually as the best way to capture events.  Sometimes they just feel sinus tachycardia and there is nothing to do.  If the palpitations are due to an ectopic atrial tachycardia (EAT), that may NOT be reproducible in the EP lab, and the only way to know this was the cause of the palpitations would be to get ECG strips from an event monitor.  If your son has already worn an event monitor and had symptoms of palpitations while wearing that, then your EP doctor has that information.  if so, you could review with them again what was seen and why the repeat EP study was performed.  If an event monitor has NOT been performed, then that should be the next step.  Additionally, if he is old enough, your son should learn how to take his own pulse rate and document how fast it is when he feels palpitations.