INTRODUCTION: New arrhythmias (NA) may appear late after accessory pathway (AP) ablation, but their relation to curative radiofrequency (RF) lesion is unknown. OBJECTIVE: The aim of this study was to determine the prevalence and predictors for NA occurrence after AP ablation and to investigate pro-arrhythmic effect of RF. METHODS: Total of 124 patients (88 males, mean age 43 +/- 14 years) with Wolff-Parkinson-White syndrome and single AP have been followed after successful RF ablation. Post-ablation finding of arrhythmia, not recorded before the procedure, was considered a NA. The origin of NA was assessed by analysis of P-wave and/or QRS-complex morphology, and, thereafter, it was compared with locations of previously ablated APs. RESULTS: Over the follow-up of 4.3 +/- 3.9 years, NA was registered in 20 patients (16%). The prevalence of specific NAs was as follows: atrioventricular (AV) block 0.8%, atrial premature beats 1.6%, atrial fibrillation 5.4%, atrial flutter 0.8%, sinus tachycardia 4.8%, ventricular premature beats (VPBs) 7.3%. Multivariate Cox-regression analysis identified (1) pre-ablation history of pathway-mediated tachyarrhythmias >10 years (HR = 3.54, p = 0.016) and (2) septal AP location (HR = 4.25, p = 0.003), as the independent predictors for NA occurrence. In four NA cases (two cases of septal VPBs, one of typical AFL and one of AV-block) presumed NA origin was identified in the vicinity of previous ablation target. CONCLUSION: NAs were found in 16% of patients after AP elimination. In few of these cases, late on-site arrhythmic effect of initially curative RF lesion might be possible. While earlier intervention could prevent NA occurrence, closer follow-up is advised after ablation of septal AP.
INTRODUCTION: New arrhythmias (NA) may appear late after accessory pathway (AP) ablation, but their relation to curative radiofrequency (RF) lesion is unknown. OBJECTIVE: The aim of this study was to determine the prevalence and predictors for NA occurrence after AP ablation and to investigate pro-arrhythmic effect of RF. METHODS: Total of 124 patients (88 males, mean age 43 +/- 14 years) with Wolff-Parkinson-White syndrome and single AP have been followed after successful RF ablation. Post-ablation finding of arrhythmia, not recorded before the procedure, was considered a NA. The origin of NA was assessed by analysis of P-wave and/or QRS-complex morphology, and, thereafter, it was compared with locations of previously ablated APs. RESULTS: Over the follow-up of 4.3 +/- 3.9 years, NA was registered in 20 patients (16%). The prevalence of specific NAs was as follows: atrioventricular (AV) block 0.8%, atrial premature beats 1.6%, atrial fibrillation 5.4%, atrial flutter 0.8%, sinus tachycardia 4.8%, ventricular premature beats (VPBs) 7.3%. Multivariate Cox-regression analysis identified (1) pre-ablation history of pathway-mediated tachyarrhythmias >10 years (HR = 3.54, p = 0.016) and (2) septal AP location (HR = 4.25, p = 0.003), as the independent predictors for NA occurrence. In four NA cases (two cases of septal VPBs, one of typical AFL and one of AV-block) presumed NA origin was identified in the vicinity of previous ablation target. CONCLUSION: NAs were found in 16% of patients after AP elimination. In few of these cases, late on-site arrhythmic effect of initially curative RF lesion might be possible. While earlier intervention could prevent NA occurrence, closer follow-up is advised after ablation of septal AP.