Validation of CTI block with standard method (2 or 3 catheters)
The following criteria were used to define bidirectional isthmus conduction block once the patient was in SR:
- During CS pacing, complete reversal of the lateral right atrial (LRA) depolarization sequence from proximal to distal on the decapolar catheter
-During pacing from the distal electrode of the decapolar catheter, activation sequence with atrial signal recorded on the His position before the atrial signal recorded on the CS catheter
-During CS pacing, the presence of double potentials, well separated with an isoelectric line, with a minimum interval of 90 ms along the ablation line
These endpoints were reevaluated after a waiting period of at least 20 min to confirm the persistence of CTI bidirectional conduction block.