acute and longterm results of slow pathway ablation in patients with atrioventricular nodal reentrant tachycardiaan analysis of the predictive factors for arrhythmia recurrence background predictors of atrioventricular nodal reentrant tachycardia avnrt recurrence after radiofrequency ablation including the importance of residual slow pathway conduction are not known the aim of this study was to report the acute and longterm results of slow pathway ablation in a large series of consecutive patients with avnrt and to analyze the potential predictors of arrhythmia recurrence with a particular emphasis on the residual slow pathway conduction after ablationmethods the study included 506 consecutive patients with avnrt mean age 526 16 years 315 women who underwent slow pathway ablation using a combined electrophysiological and anatomical approach the end point of ablation procedure was noninducibility of the arrhythmia the primary end point of the study was the recurrence of avnrtresults acute success was achieved in 500 patients 988 after ablation 471 patients 93 were followed up for a mean of 903 692 days of the 465 patients with successful ablation 24 patients 52 developed avnrt recurrences during the followup no significant differences in the cumulative rates of avnrt recurrence were observed in groups with or without electrophysiological evidence of residual slow pathway conduction p 025 logrank test multivariate analysis identified only age as an independent predictor of avnrt recurrence hazard ratio 096 95 confidence interval 094099 p 0004 with younger patients being at an increased risk for arrhythmia recurrenceconclusions our study demonstrated that only younger age but not other clinical or electrophysiological parameters including residual slow pathway conduction predicted an increased risk for avnrt recurrence after slow pathway radiofrequency ablation