Long-term follow-up after catheter ablation for atrioventricular nodal reentrant tachycardia: a comparison of cryothermal and radiofrequency energy in a large series of patients

Abstract

BackgroundRadiofrequency (RF) catheter ablation for atrioventricular nodal reentrant tachycardia (AVNRT) is highly successful but carries a risk for inadvertent atrioventricular block. Cryoablation (cryo) has the potential to assess the safety of a site before the energy is applied.PurposeThe aim of this study was to evaluate the long-term efficacy and safety of cryothermal ablation in a large series of patients and compare it to RF.MethodsAll consecutive routinely performed AVNRT ablations from our centre between 1999 and 2007 were retrospectively analysed.ResultsIn total, 274 patients were elegible: 150 cryoablations and 124 RF. Overall procedural success was 96% (262/274), and equal in both groups, but nine patients were crossed to another arm. Mean fluoroscopy time was longer in the group treated with RF (27 ± 22 min vs. cryo 19 ± 15 min; p = 0.002). Mean procedure time was not different (RF 138 ± 71 min vs. cryo 146 ± 60 min). A permanent pacemaker was necessary in two RF patients. The questionnaire revealed a high incidence of late arrhythmia related symptoms (48%), similar in both groups, with improved perceived quality of life. The number of redo procedures for AVNRT over 4.3 ± 2.5-years follow-up was not statistically different (11% after cryo and 5% after RF).ConclusionsOur data confirm that cryo and RF ablation with 4-mm tip catheters for AVNRT are equally effective, even after long-term follow-up.

Single center experience of fluoroless AVNRT ablation guided by electroanatomic reconstruction in children and adolescents

“…The overall long-term success rate using fluoroless cryoablation was 92% (24/26 procedures), similar to the success rate for RF ablation [33][34][35][36] . However, this result has been achieved performing a second fluoroless cryoablation procedure in 3 patients.…”

Cryoablation of typical AVNRT: Younger age and administration of bonus ablation favor long-term success

“…Before performing the electrophysiological study (EPS), the clinical diagnosis of typical AVNRT was based on the (1) history of a regular narrow complex tachycardia documented by electrocardiogram (ECG), Holter monitoring, transient arrhythmia monitoring, or other cardiac rhythm strip; (2) absence of identifiable P waves or presence of small terminal retrograde P waves that are not present in sinus rhythm 9 ; and (3) exclusion of manifest accessory pathway and/or other atrial tachycardias. Patients who had previously undergone any ablation procedures (with either source of energy) and those with structural heart disease were excluded from the present study.…”

“…[1][2][3] Cryomapping (CM), performed by decreasing the temperature at the catheter tip to À301C, enables the assessment of functional electrophysiological effects of ablation before the execution of a permanent lesion. 4 In this way, the targeted site may be confirmed safe for ablation.…”

Catheter Cryoablation

“…In a systematic review that combined 22 published studies (including 2654 patients), cryothermal ablation had a high procedural success rate (95%; range, 85%-99%) that was comparable with RFCA (95%-98%). [30][31][32][35][36][37][38][39][40][41][42][43][44][45][46][47] Long-term freedom from recurrent arrhythmia with cryoablation was reported to be 89% (range, 81.3%-98%), which was lower than historical observations with RF (3%-7% recurrence). 32 Although historical comparisons between observational studies are fraught with potential biases, 11 comparative studies between cryothermy and RFCA for AVNRT (8 retrospective observational studies and 3 prospective randomized studies; Table 1), reported comparable acute success rates.…”

“…32 Although historical comparisons between observational studies are fraught with potential biases, 11 comparative studies between cryothermy and RFCA for AVNRT (8 retrospective observational studies and 3 prospective randomized studies; Table 1), reported comparable acute success rates. [36][37][38][39][40][41][42][43][44][45][46][47] Although the longer term recurrence rate was statistically similar in 7 of the 11 studies, there was an overall trend that favored RFCA. Procedural duration was globally similar, with a shorter fluoroscopy time with cryoablation.…”