环肺静脉电隔离术后未达消融终点的房颤患者心外膜电传导观察及意义

Study of epicardial electrical conduction in patients with atrial fibrillation no achieve the endpoin after circumferential pulmonary vein ablation

目的观察环肺静脉电隔离术后未达消融终点的房颤患者心外膜电传导特点,并探讨其意义。方法选择因心房颤动行环肺静脉电隔离术的患者54例,对完成环肺静脉线性消融而未达消融终点者进行详细的电标测、起搏验证及巩固消融,并记录其心脏CT扫描及三维重建资料。结果 54例患者中,5例完成左侧环肺静脉电隔离术时见肺静脉电位脱落,术后验证仅左上肺静脉深处可记录一个复现延迟的肺静脉电位。电生理证实该电位通过左上肺静脉深处前壁与左心耳后壁之间的心外膜传导,仅在肺静脉前庭阻断后显现,为延迟的双向缓慢传导。2例在左上肺静脉深处前壁或左心耳后壁消融能阻断电传导。心脏CT扫描及三维重建分析显示,5例患者的左心耳后壁与左上肺静脉深处前壁紧密贴靠。结论环肺静脉电隔离术后未达消融终点的房颤患者存在左心耳后壁与左上肺静脉前壁间的心外膜电传导,在肺静脉前庭电隔离后方能显现。该电位对房颤消融成功率有影响,心脏CT可显示其影像学基础。

Objective To observe the characteristic of the epicardial electrical conduction in patients with atrial fibrillation no achieve the endpoint after circumferential pulmonary vein ablation,and to discuss its significance. Methods 54 patients with atrial fibrillation underwent circumferential pulmonary vein ablation were included in the study. The patients no achieve the endpoint after circumferential pulmonary vein ablation were consolidated the ablation line,paced and mapped in the left atrial appendage（ LAA） and left superior pulmonary vein（ LSPV）,also collected the data of computer digital tomography（ CT） of heart. Results Though the pulmonary vein potential（ PVP） loss while the accomplishment of circumferential pulmonary vein ablation for left pulmonary vein（ LPV）,a sharp and delay recurrent PVP could be recorded in LSPV while verification after ablation in 5 patients. It was confirmed to be a epicardial electrical conduction through the LAA and LSPV,by electrophysiologic study. It was a delayed,slow bidirectional conduction,and just appeared after the pulmonary vein antrum isolation. 2 cases might be finally blocked by ablation in posterior wall of LAA or anterior wall of depths of LSPV. CT of heart showed that the space was narrow between the LAA and the LSPV,and the LAA-LSPV connections could be seen. Conclusions The epicardial electrical conduction between the posterior wall of LAA and the anterior wall of depths of LSPV would just appear after the circumferential pulmonary vein isolation,that the pulmonary vein antrum was isolation,but didnt achieve the endpoint of ablation. The success rate of ablation was affected by the electrical conduction. The cardiac CT can showed the imaging foundation of it.