Distal end of the atrioventricular nodal artery predicts the risk of atrioventricular block during slow pathway catheter ablation of atrioventricular nodal reentrant tachycardia

Abstract

AVNRT is the most common form of SVT. RF ablation of the slow pathway has been proved to be the most safe and effective modality of the treatment of AVNRT. Major drawbacks were recurrence and haert block. Permenant CHB is rare, however transient CHB IS common . Unless the delivery of the RF current is immediately interrupted , the risk of permenant damage to the AV node is high.

Our study included 20 cases complaining of recurrent palpitation and referred for EPS and ablation in whom the underlying rhythm disorder was AVNRT.

All cases underwent successful ablation of the SP of AVNRT. 2 cases were complicated with heart block. The first had irreversible first degree AV block, while the second had transient complete HB followed by first degree AV block.

Selective coronary angiography in RAO and LAO 30 was done for all patients to demonstarte the distal end of the AV nodal artery..

The artery was identified as a branch from the distal part . of the RCA at the level of the "U" turn of James. The artery was single ended or fork tailed and in the latter case the distal end was taken as midway between the 2 ends.