慢性心房颤动消融术后房性心动过速的机制和消融治疗

The treatment of recurrent atrial tachycardia originated from left atrium after continuous circular lesious around the ipsilateral pulmonary veins in patients with chronic atrial fibrillation

目的探讨慢性心房颤动（房颤）环肺静脉消融术后房性心动过速（房速）的机制及射频消融的方法。方法慢性房颤消融术后房速患者9例，均为男性，年龄50-70（62．6±7．2）岁。在三维标测系统和环状标测导管联合指导下，对无心房-肺静脉电传导者的房速经标测在关键峡部消融；对存在心房-肺静脉电传导者的房速，在原消融径线上的裂隙处消融。结果3例为无心房-肺静脉点传导的折返性房速，于关键峡部线性消融后房速终止；6例为存在心房-肺静脉电传导的房速，对原消融径线裂隙消融后，4例房速终止，余2例附加左心房峡部线性消融后房速亦终止。消融术时间为90-295（211．7±75．4）min，X线曝光时间为11．5～67．6（25．5±16．5）min。消融术后各种刺激亦均不能诱发房速，没有出现肺静脉狭窄和其他相关并发症。随访4～8（6．2±1．4）个月，9例患者停用抗心律失常药物后仍为窦性心律。结论慢性房颤消融术后恢复心房-肺静脉电传导的房速（66．7％）占大多数；无心房-肺静脉电传导的房速多为折返机制；针对恢复传导部位的补点式消融和对折返环关键峡部的线性消融，可以成功终止并发的房速。

Objective To evaluate the radiofrequency （RF） ablation for the recurrent atrial tachycardia （AT） originated from left atrium （LA） after continuous circular lesions （CCLs） around the ipsilateral pul- monary veins （PVs） in patients with chronic atrial fibrillation （AF）. Methods A repeat procedure was per- formed in 9 patients [9 males ; age 50 - 70 （ 62. 6±7.2 ）] with recurrent AT. In this procedure, LA-PV conduction was confirmed by Lasso catheter. If no LV-PV conduction, activation mapping and entrainment technique were performed with 3-D Carto system to identify the earliest activation area and reentrant circuit. If LV- PV conduction recovered, the gap on the original CCLs was confirmed and was blocked again. Results No LA- PV conduction in the 3 patients and LA-PV conduction in 6 patients were demonstrated. In the 3 patients with- out LA-PV conduction, reentrant AT was confirmed and was successfully abolished by blocking the reentrant circuit. In the other 6 patients with LA-PV conduction, all conduction gaps were successfully closed with segmental RF ablation. Recurrent AT was successfully terminated in 4 patients and changed to maeroreentrant AT in the other 2 patients. Following blocked the LA isthmus to terminate remained AT. The duration of the procedure was 90-295 （ 211.7±75.4） min and the duration of X-ray was 11.5 - 67. 6 （25.5±16. 5 ） min. During follow-up of 4-8 （6. 2±1.4） months, all 9 patients were free of AT without antiarrhythmic drugs. Conclusions In patients with recurrent AT after CCLs for chronic AF, AT without recovered LA-PV is complicated and can be abolished by mapping and ablation of reentrant circuit ; AT with recovered LA-PV conduction （ 66. 7% ） is a dominant finding and can be successfully eliminated by segmental RF ablation.