AVNRT: Dual AV node physiology AVNRT Normal Sinus Rhythm During sinus beats • conduction occurs via fast pathway • conduction via slow pathway is blocked What happens with AVNRT is that patients have two conduction pathways through the AV node a fast pathway and a slow pathway and normally the fast pathway wins out

AVNRT: Initiation of tachycardia And as this circuit spins around the AV node, it sends impulses up the atrium and down the ventricule since the A and V are activated simultaneously, and getting that P wave, right after the QRS is virtually diagnostic for AVNRT

58 yo male who presents to ED with light headness after Mitral Valve Replacement Often though, you will just see a regular NCT with no clear P waves, as the P waves are literally barried in this QRS complex

AVNRT: Catheter ablation AVNRT can be cured permanently with catheter ablation, using radio frequency to heat and destroy the cells in the slow pathway, creating a permanent line of block. To treat the arrhtymia, you can try to use medications such as beta blockers or Ca channel blockers to suppress the connection through the AV node. But if the pt has symptoms, I usually move on to catheter ablation, Where we ablate the slow pathway, leave the fast pathway alone and this is really a simple and curative procedure and in my opinion, a couple of hours to have this done on an outpaient basis is better than a lifetime of medications