Ablation for AVNRT

My ep believes that my afib episodes are being stimulated by an AVNRT (as deduced by monitoring for one month), and that an ablation for the AVNRT will either eliminate or greatly reduce the afib episodes (first episode was on 7/23/07).  Went in for an eps and ablation yesterday, but after three hours, my ep said he was unable to elicit the AVNRT, even though he was very aggressive and took heart rate to 300 bps.  I had an svt/afib episode four days prior to procedure where episode was terminated with cardizem drip in ER in 60 min.  Took a cardizem CD next day, and then was off meds for nearly two and a half days prior to procedure (Dr. asked me to discontinue for 4 days prior.)   Could the cardizem in or additional cardizem CD have caused the problem with eliciting the AVNRT during the procedure?  My doctor says that he's had this happen only one time previously.  I also took xanax for the three days between ER visit and eps/ablation due to anxiety-could this have caused the problem?  I disclosed my med history when I checked in for the procedure.  Thank you in advance for your response.

[Michael J. McWilliams, M.D.]

Could the cardizem in or additional cardizem CD have caused the problem with eliciting the AVNRT during the procedure?  

Beta blockers and calcium channel blockers can make it more difficult to induce AVNRT and similar arrhythmias. It is possible that the medications impaired their ability to induce an arrhythmia.

I also took xanax for the three days between ER visit and eps/ablation due to anxiety-could this have caused the problem?

The affects of xanax can usually be over powered with medications like isoproterenol during the ablation.  Xanax is so short acting I doubt it affecting the ability to induce.

If he has good strips to suggest you have AVNRT then it is reasonable to try again off medications.  It is also possible that you atrial tachycardia or atrial flutter, but you doctor would know better because they have access to the EKGs.

It is known that rhythms like AVNRT, AVRT, and atrial flutter can induce atrial flutter.

I hope this helps.  Good luck.