正常犬左束支射频消融的实验研究

射频消融 (RFCA)左束支可以治愈少数束支折返性室性心动过速 ,并可能作为减轻肥厚型梗阻性心肌病左室流出道压力阶差的一种方法。为探讨射频导管消融左束支的方法及其可行性、安全性。对 15条犬心左束支施行RFCA ,9条犬成功消融左束支、5条犬发生完全性房室阻滞 (AVB)、1条犬造成右束支阻滞。研究发现 9条消融成功犬心损伤灶位于右冠瓣与无冠瓣交界区下方 1～ 2cm ,Ⅲ度AVB者位于右冠瓣和无冠瓣的交界处 ,右束支者消融靶点位于主动脉瓣无冠瓣和右冠瓣交界处靠前处。研究还发现仅以标测到的左束支电位难以准确消融左束支 ,而单纯以X线影像定位就能成功阻断左束支。左束支阻断后 ,可以造成室间隔的异常运动。

Study of Blocking of Left Bundle Branch With Radiofrequency Catheter Ablation in Normal Canines．

A few of bundle branch reentrant ventricular tachycardias can be cured by means of ablating Left bundle branch (LBB) with radiofrequency current.Radiofrequency catheter ablation(RFCA) can also decrease pressure gradient of left ventricular outflow in patients with obstructive hypertrophic cardiomyopathy.The purpose of this study was to investigate feasibility,safty and methodology of LBB ablating by RFCA,and changes of movement of ventricular walls after LBB blocked.There were 15 normal canines for study,The LBB were blocked with RFCA in 9 canines,the complete atrioventricular block(AVB) occurred in 5 canines and right bundle branch block(RBBB) occurred in 1 canine.The results showed that ablation point of 9 canines with LBB block(LBBB) situated at 1～2 cm below the connection site of right coronary valve and noncoronary valve,5 canines with complete AVB situated at connection site of right coronary valve and noncoronary valve,1 canines with RBBB situated at foreside connection site of right coronary valve and noncoronary valve.The results showed that it was difficult to ablate left bundle branch accurately only guided by left bundle branch potential,but it was successful to ablate it and to preventing complete AVB with the X ray image localization.Diskinesia of interventricular septum appeared after LBB blocked.