Marazzato Jacopo, Fonte Giuseppe, Marazzi Raffaella, Doni Lorenzo A, Mitacchione Gianfranco, Vilotta Manola, De Ponti Roberto
Department of Heart and Vessels, Ospedale di Circolo e Fondazione Macchi, University of Insubria, Viale Borri, 57, 21100, Varese, Italy.
J Interv Card Electrophysiol. 2019 Jun;55(1):47-54. doi: 10.1007/s10840-018-0498-9. Epub 2019 Jan 3.
Radiofrequency (RF) catheter ablation of para-Hisian (P-H) and mid-septal (M-S) accessory pathways (APs) is a potentially harmful procedure due to their close location to the A-V node. Conversely, cryoablation (CA) appears safer in this setting. The aim of this study was to assess the efficacy and safety of CA of these APs using a specific protocol.
Fifty-three patients undergoing CA for P-H (45) or M-S (8) APs were included. CA was performed with a 4-mm catheter at - 75 °C for 480 s in the site where conduction block over the AP was obtained by a specific cryomapping protocol. Optimal catheter-tissue contact was achieved by inferior or superior vena cava approach. In case of failure, a 6-mm catheter and/or trans-septal catheterization (TSC) were considered. Normal AV conduction was monitored throughout CA, which was interrupted in case of its inadvertent modifications.
In 46 patients (87%), CA was successful. Reasons for failure were as follows: lack of AP interruption (3 patients), intraprocedure AP conduction resumption (3), or transient A-H interval prolongation (1). Failure was associated with more aggressive approach including multiple procedures, greater use of 6-mm catheters, TSC, and longer CA applications. No major complications were observed. Three out of 46 patients (6.5%) experienced relapse of AP conduction during follow-up and were successfully re-treated by CA.
CA of P-H and M-S APs is highly safe and effective and a specific protocol for cryomapping and CA could lead to a low recurrence rate at follow-up.
由于希氏束旁（P-H）和中隔部（M-S）旁路（APs）靠近房室结，射频（RF）导管消融这些旁路是一种潜在有害的操作。相反，在这种情况下，冷冻消融（CA）似乎更安全。本研究的目的是使用特定方案评估这些旁路冷冻消融的疗效和安全性。
纳入53例接受P-H（45例）或M-S（8例）旁路冷冻消融的患者。通过特定的冷冻标测方案在获得旁路传导阻滞的部位，使用4毫米导管在-75°C下进行480秒的冷冻消融。通过下腔静脉或上腔静脉途径实现最佳导管与组织的接触。如果失败，则考虑使用6毫米导管和/或经房间隔插管（TSC）。在整个冷冻消融过程中监测正常房室传导，若出现意外改变则中断操作。
46例患者（87%）冷冻消融成功。失败原因如下：旁路未中断（3例）、术中旁路传导恢复（3例）或短暂的A-H间期延长（1例）。失败与更积极的方法有关，包括多次操作、更多地使用6毫米导管、TSC以及更长时间的冷冻消融应用。未观察到重大并发症。46例患者中有3例（6.5%）在随访期间出现旁路传导复发，并通过冷冻消融成功再次治疗。
P-H和M-S旁路的冷冻消融高度安全有效，特定的冷冻标测和冷冻消融方案可导致随访时低复发率。
