Paediatric catheter cryoablation: techniques, successes and failures

The benefit of transcatheter cryoablation over radiofrequency ablation is its ability to find the most suitable site for ablation through transitory electrical paralysis of the heart tissue in contact with the catheter tip, frozen to −30°C (cryomapping). Cryoablation is thus ‘made to measure’ for paediatric patients. The purpose of this review is to show the results of cryoablation in the literature in order to understand when it can be used in children as an alternative to radiofrequency ablation. Modified cryoablation protocols have increased acute success rates and decreased recurrences. Single institutions, comparing the results obtained with cryoablation and radiofrequency ablation for the treatment of supraventricular arrhythmias, have demonstrated the same success rate. Furthermore, some authors have attempted to identify parameters predictive of efficacy during cryoablation of atrioventricular nodal re-entry tachycardia. On the basis of the more recent literature data, cryoablation should be considered the treatment of choice for atrioventricular nodal re-entry tachycardia and atrioventricular re-entry tachycardia caused by an accessory pathway very close to the atrioventricular junction in school-age children. The short and long-term efficacy of cryoablation is correlated with highly accurate cryomapping and the creation of a stable lesion through consolidation of the first effective lesion.