选择性消融逆传快径治疗典型房室结折返性心动过速

设计一种新的射频消融方法（选择性消融逆传快径）对25例反复发作的典型房室结折返性心动过速（AVN－RT）进行消融治疗。经股静脉插入1～2很大头电极至Koch氏三角区，于旁His束心室起搏下寻找还传A’最早的靶点，靶点图上不能有或仅有极小H波，大头电极用力压向靶点出现：①VA分离或H’A’间期延长，说明逆传快径已被机械刺激所阻断，立即放电15～25W，持续30～90S；②AH间期延长，说明前传快径已被机械刺激所阻断，移开大头电极待AH间期恢复正常，再重新标测；③反复数次操作，大头电极的机械刺激仍不能阻断逆传快径，则选择逆传A’最早的靶点试放电30S，出现VA分离或H’A’间期延长，则放电至60～90s，否则重新标测靶点。消融终点为VA分离或H’A’间或延长，用异丙肾上腺素仍不能诱发典型和非典型AVNRT。25例均一次消融成功，逆传快径被阻断、前传慢径均保留；23例VA分离、2例仅有H’A’间期延长；6例前传快径阻断；4例病人术中大头电极的机械刺激阻断了逆传快径。1倒成功靶点位于His束电极后上方，24例位于His束电极与冠状窦电极之间的区域。结论：在仔细精确的电生理标测下可实现选择性消融逆传快径，保留前传快慢径。此方法安全有效。

Selective Transcatheter Ablation of the Retrograde Fast Pathway Using Radiofrequency Energy in Patients With Atrioventricular Nodal Reentrant Tachycardia

A new hypothesis is proposed that it may be possible to selectively ablate retrograde fast pathway to cure typical atrioventricular nodal reentrant tachycardia (AVNRT). Twenty-five patients with typical AVNRT were included in the current study. One or two ablation catheters were inserted to Koch's triangle through femoral vein. The earliest retrograde A' target site was sought under para-His pacing. There was no or very little H wave at the target site. Torque was applied to the ablation catheters and pressure the target site.① VA dissociated or H' A' prolonged,it meant that retrograde fast pathway was blocked by ablation catheter mechanical trauma. Radiofrequency energy (15-25 W, 30-90 s) was applied to the target site. ② AH prolonged,it meant that anterograde fast pathway was blocked by ablation catheter mechanical trauma. Ablation catheter was removed waiting restore of anterograde fast pathway conduction. ③ After multiple attempts retrograde fast pathway was not blocked by mechanical trauma,radiofrequency energy (15-25 W, 30 s ) was applied to the optimal target site. If VA dissociated or H' A' prolonged,another pulse (60- 90 s ) was applied to that site. lf neither VA dissociated nor H' A' prolonged,remapping was needed. The retrograde fast pathway was removed and the anterograde slow pathway reserved in all patients. VA was dissociated in 23 and H' A' was prolonged in 2 patients. Six patients also had anterograde fast pathway damage. There was no other complication.The successful site was located upper to His catheter in one patient and between His and coronary sinus catheter in another 24 patients. This result indicates that under accurate mapping it is Possible to selectively ablate retrograde fast pathway to cure typical AVNRT.