射频消融治疗房室结折返性心动过速的方法学研究——判断慢径阻断的新指标

改良房室结折返性心动过速 (AVNRT)慢径消融的方法学 ,以探讨判断慢径阻断的新指标。 6 0例AVNRT病人接受慢径射频消融术 ,根据X线影像部位和局部电图特点确定消融靶点 ,心房快速刺激 (S1S1)显示慢径前传放电消融 ,以 10s内慢径前传阻滞作为有效消融指标并以此连续放电达 30s。消融后房室结双径传导消失 ,不再诱发AVNRT为手术终点。 6 0例病人均达到消融终点。共消融 36 1个靶点 ,其中放电不足 10s者 2 80个、放电 30s者 81个 ,后者中 6 0个为有效消融靶点。有效阻断慢径者表现为放电 6 .9± 1.8(2 .8～ 10 )s慢径前传阻滞 ,S1刺激经快径前传。所有病人术后 3～ 7天食管电生理复查不再诱发AVNRT。随访 3～ 19个月无AVNRT复发。结论 :显示慢径前传消融可客观判断放电消融的有效性 ,避免盲目延长放电时间所造成的无效心肌损伤

Methodology of Selectiv e Slow Pathway Ablation With Radiofre-quency Current for Treatment of Atriovent ricular Nodal Reentrant Tachycardia :A New Criterion for Monitoring Slow Pathwa y Block

In order to study a new criterion for monitoring slow pathway block,a modified approach was used to ablate slow pathway with radiofrequency current for treating patients with atrioventricular nodal reentrant tachycardia (AVNRT).60 patients with AVNRT underwent radiofrequency current catheter ablation (RFCA) for blocking slow pathway.The ablation targets were localized according to characteristics of X ray image and local electrograms.Radiofrequency current was delivered to the target during S 1S 1 atrial pacing to show conduction of slow pathway.Slow pathway conduction block within 10 seconds delivering was the sign of slow pathway damage and then delivering continued up to 30 seconds.The end point of the approach was to eliminate AVNRT and dual atrioventricular node pathway conduction.Results:The approaches reached end point in all patients.361 targets were ablated,including 280 targets which were delivered less than 10 seconds and 81 targets which were delivered up to 30 seconds.60 of 81 targets were successful ablation sites.Slow pathway conduction was blocked during 6.9±1.8(2.8～10) seconds delivery in all successful targets and conduction was only through fast pathway.During transesophageal left atrial electrophysiological test,there was no inducible AVNRT 3 to 7 days after procedure.There was no AVNRT recurrence in 13.9±4 monthes follow up.Conclusions:Delivering to targets during showing slow pathway conduction is useful method to monitor objectively the efficiency of slow pathway ablation,which prevent myocardial damage from delivering too long.