Mapping and ablation of RVOT-type arrhythmias: comparison between the conventional and reversed U curve methods

Purpose We assessed conventional and reversed U curve methods for mapping and ablation of RVOT-type VAs.Methods Single-center data were reviewed from consecutive cases of symptomatic VAs of RVOT-type origin that were mapped and ablated successfully using conventional method in RVOT (pulmonary artery might be included) from January 2014 to December 2015 (cohort 1, n = 75) or conventional method in RVOT and reversed U curve in PSC (for first ablation attempt) from January 2016 to March 2017 (cohort 2, n = 60).Results At least 90% of RVOT-VAs could be eliminated using conventional method in RVOT or reversed U curve in PSC. For RVOT-VAs, if the earliest activation site was in midposterior free wall, midposterior septal side of RVOT, or anterior free wall/septal side of RVOT with conventional method, it was likely eliminated in right, left, and anterior PSC with reversed U curve method, respectively. Nearly the same earliest potential in almost the same region could be recorded by both methods. Compared with conventional method, the reversed U curve method showed better catheter stability and contact force during mapping and ablation, and showed distinctive features in presystolic potential recording, unipolar mapping, and ablation response.Conclusions Most of RVOT-VAs could be eliminated using conventional method in RVOT or reversed U curve in PSC. However, the reversed U curve method has superiority in catheter stability and contact force, especially for VAs form free wall of RVOT.

目的：我们评估了用于右心室流出道（RVOT）型室性心律失常（VAs）标测和消融的常规方法及倒“U”曲线法。 方法：回顾了单中心2014年1月至2015年12月使用RVOT常规方法（可能包括肺动脉）成功标测和消融的RVOT型起源的症状性VAs连续病例（队列1，n = 75），以及2016年1月至2017年3月使用RVOT常规方法和肺动脉窦（PSC）倒“U”曲线法（首次消融尝试）的病例（队列2，n = 60）的数据。 结果：使用RVOT常规方法或PSC倒“U”曲线法至少可消除90%的RVOT - VAs。对于RVOT - VAs，如果使用常规方法最早激动部位在RVOT的中后游离壁、中后间隔侧，或RVOT的前游离壁/间隔侧，那么使用倒“U”曲线法分别可能在右、左和前PSC处消除。两种方法几乎可在相同区域记录到几乎相同的最早电位。与常规方法相比，倒“U”曲线法在标测和消融过程中显示出更好的导管稳定性和接触力，并且在收缩前电位记录、单极标测和消融反应方面具有独特特征。 结论：使用RVOT常规方法或PSC倒“U”曲线法可消除大多数RVOT - VAs。然而，倒“U”曲线法在导管稳定性和接触力方面具有优势，特别是对于源自RVOT游离壁的VAs。