AimsCryoablation is an effective treatment for children with an accessory pathway (AP). Nevertheless, AP may recur after a successful procedure. The aim of this study was to identify the factors predictive of AP recurrence.Methods and resultsThirty patients (mean age 12.6 ± 2.9 years) with acutely successful cryoablation of supraventricular tachycardia caused by a right-sided AP were studied. In 20 patients, a lengthier cryoablation and a single 'bonus' cryoapplication to consolidate a permanent lesion were delivered. During the follow-up (mean duration 20 months, range 4-25), no permanent cryo-related complications occurred. Accessory pathway recurrence was observed in six patients (20) overall, specifically in 30 of patients who did not undergo a bonus cryoapplication and in 15 of the others. The likelihood of AP recurrence was correlated with the 'time to effect' (TTE), i.e. the time interval between the onset of cryomapping at -30°C and the disappearance of AP conduction. The mean TTE in the patients without AP recurrence was 8.2 ± 8.4 s, in contrast with 16.7 ± 9.8 s in the others (P = 0.04). The receiver-operating characteristic (ROC) curve of TTE values demonstrates that if the pathway does not lose its conduction capacity until 10 s after reaching -30°C, the probability of arrhythmia recurrence is higher (area under curve = 0.767, sensitivity 83.3, and specificity 66.7).ConclusionThe long-term success of cryoablation of right-sided AP is closely correlated to the TTE during cryomapping.
- Accessory pathway
- Supraventricular tachycardia
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine
- Physiology (medical)