This is a randomized study on the safety and efficacy for percutaneous ablation of para-hisian accessory pathways according to two different modalities: radiofrequency (RF) or cryotherapy.~Thirty patients with symptomatic or high-risk para-hisian accessory pathways, documented by previous electrophysiological study (EPS), referred to percutaneous catheter ablation, will be enrolled in this trial.~After informed consent, these patients will be randomized in 2 groups with different current established strategies of invasive treatment. Group I: electrophysiological mapping and ablation with radiofrequency (RF) focal lesion formation.~Group II: electrophysiological mapping and ablation with cryotherapy (CRYO) focal lesion formation.~The primary outcome will be the recurrence rate of accessory pathway conduction after one year of follow-up. Secondary endpoints will be immediate success and rate of permanent atrioventricular (AV) block.
A randomized pilot study to evaluate safety and efficacy endpoints for treatment of para-hisian accessory pathways according to two different strategies of lesion formation.~These patients will be divided into 2 groups with different strategies of treatment: group 1 treated with radiofrequency (RF) ablation, group 2 with cryotherapy (CRYO).~The primary outcome will be the recurrence rate of accessory pathway conduction after one year of follow-up. Secondary endpoints will be immediate success and rate of permanent atrioventricular (AV) block.