非接触标测系统用于典型心房扑动的右房标测和导航消融

应用非接触标测系统实施典型心房扑动 (AFL)的右房 (RA)全心腔标测和导航射频消融。 6例典型AFL ,男 5例、女 1例 ,年龄 5 6 .2± 15 .3(35～ 76 )岁。常规放置冠状静脉窦和His束电极 ,将标测球囊置于RA中下部 ,构建RA心内膜模型 ,分别于低位RA和冠状窦口 (CSO)S1S16 0 0ms起搏观察峡部传导 ,诱发并标测AFL的激动顺序和折返路径。 1例为顺钟向AFL ,4例为逆钟向AFL ,1例未能诱发AFL。AFL周期 2 0 7± 34ms,非接触标测可显示整个折返环路、激动顺序和缓慢传导区。AFL的激动可以穿过界嵴上部并且传导相对缓慢 ,提示RA平滑部是折返环的一部分。后位峡部线性消融在导航系统指导下进行 ,无需X线透视。消融完成后重复上述起搏验证峡部双向传导阻滞。除 1例术中出现心房颤动 (AF)外 ,其余病例即刻均达到峡部双向阻滞 ,未出现其他并发症 ,随访 8.1± 6 .7(3～15 )个月未见复发。非接触标测系统可安全、有效和直观地实现典型AFL的右房全心腔标测并导航消融 ,验证峡部双向阻滞 ,减少X线曝光时间和无效放电次数。界嵴在典型AFL时具备传导功能 ,RA平滑部和粗糙部共同参与折返环的组成。

Global Mapping of Right Atrium and Navigated Radiofrequency Ablation in Typical Atrial Flutter Using Non-contact Mapping System

The aim of this study is to describe the global right atrium(RA) mapping of typical atrial flutter (AFL) and navigated radiofrequency ablation method.In 6 patients with typical AFL,the non contact mapping balloon was deployed in RA,and three dimensional endocardial geometry of RA was established.Isthmus conduction was mapped during the ostium of the coronary sinus (CSO) and low RA (LRA) pacing with 600ms cycle length.Thereafter,atrial activation of spontaneous or induced flutter was mapped to identify the activation sequence and reentrant way within the RA.A clockwise moving reentrant activation wavefront through the isthmus in 1 of the 6 patients was observed and a counter clockwise rotating wavefront in 4 of the 6 patients,respectively.AFL was not inducible in one patient.The cycle length of AFL was 207±34 ms.The whole reentrant cycle,activation sequence,and slow conduction zone was displayed by non contact mapping.In each mapped AFL,the wavefront conducted through the superior part of crista terminalis (CT) and propagated slowly,which indicated that the smooth part of RA was involved in the reentrant circuit.Linear isthmus radiofrequency ablation was guided by navigation system without fluoroscopy,and isthmus bidirectional block was verified by pacing CSO and LRA.Complete isthmus bidirectional conduction block was achieved at the end of the procedure except one case because of atrial fibrillation,and no other complication was observed.No recurrences of AFL occurred during follow up of 8.1±6.7 months.In conclusion,the use of non contact mapping system in patients with typical AFL is safe,directed visualize and highly effective.This system allows global detailed mapping of RA,navigated ablation without fluoroscopy,verifying isthmus bidirectional conduction block,and reducing fluoroscopy time and unnecessary ablation.CT,which was previously supposed to be a complete conduction barrier,was now proved to be of transverse conduction by noncontact mapping,and smooth and trabeculated part of RA participate the reentrant of typical AFL simultaneously.