Long term success of slow pathway ablation
Feldman et al reported high long-term success with slow pathway ablation
in 1419 patients with AVNRT31. Independent predictors
of AVNRT recurrence were age < 20 years and female gender. No
significant difference in the incidence of late recurrence was observed
in presence or absence of residual slow pathway conduction, use of
isoproterenol testing or general anaesthesia31.
Katritis et al reported non inducibility despite isoproterenol challenge
as the most reliable predictor of clinical success in a retrospective
analysis of 1007 patients who underwent RFA for
AVNRT8. The presence of junctional rhythm during
ablation was highly sensitive but not specific for procedural success
nor was the presence of residual slow pathway conduction. Jentzer et al
reported the individual response to RFA 26 in 52
patients with AVNRT. RF was delivered for 20-40seconds prior to testing
and terminated prematurely in the presence of JA block. In keeping with
the present study, procedural success was associated with a longer
duration of junctional beats and total number of junctional beats but
not the cycle length of JR. EP testing was only performed if RF was
delivered for ≥ 20 seconds and included some cases retrospectively.