Purpose: The aim of this study is to verify whether the persistence of conduction over the slow pathway is related to an increased trend for recurrence.
Methods: Recurrence rate was retrospectively analyzed in 126 patients who underwent slow pathway radiofrequency (RF) catheter ablation during a follow-up of 20 +/- 12 months. The ablative procedure was interrupted when AVNRT was no longer induced by atrial stimulation after intravenous infusion of isoproterenol. Ninety-eight patients had no evidence of slow pathway whereas 28 patients persisted with AV node jump and atrial echo beat.
Results: There were 15 recurrences: 9% of those who had no evidence of slow pathway (9 of 98 patients) and 21% of those with AV node jump and/or atrial echo beat but this difference was not statistically significant.
Conclusion: As long as AVNRT cannot be induced by atrial pacing and isoproterenol infusion after slow pathway RF catheter ablation, the presence of AV node jump and/or atrial echo beat does not increase the risk of recurrence of AVNRT.