射频消融慢径后房室结电生理特性变化的探讨

Electrophysiological Changes of Atrioventricular Node After Radiofrequency Ablation by Slow Pathway

目的:探讨房室结折返性心动过速(AVNRT)患者消融慢径对房室结电生理特性的影响。方法:①比较34例患者射频消融术前及术后AH间期、房室结前传及逆传文氏周期、快径路及慢径路前传有效不应期。②根据术后慢径是否消失将34例患者分为:慢径消失组(n=24);慢径改良组(n=10),比较两组间快径及慢径前传有效不应期。结果:房室结改良前后文氏周期变化:34例患者在未分组前射频消融前后房室结文氏周期无明显变化。快径前传有效不应期:慢径消失组快径前传有效不应期术后较术前降低,有显著性差异(P<0．05);慢径改良组慢径前传有效不应期术后较术前延长,有显著性差异(P<0．05)。结论:快径前传有效不应期的缩短与消融后慢径是否残存有关;慢径的消融影响房室结的前向传导。

Objective： To investigate the electrophysiological changes of the atrialventricular node（AVN） after radiofrequency catheter ablation （RFCA） by slow pathway in patients with AVN reentrant tachycardia（AVNRT）. Methods： ①The AH interval, AVN antegrade and retrograde Wenckbach＇ s block points（ms） of 34 patients before and after RFCA were compared. ②The patients with AVNRT were divided into two groups according to weather slow pathway was eliminated. In group A （n =24） ： slow pathway was completely eliminated. In group B （n = 10） ：slow pathway was modified. The fast pathway and slow pathway antegrade effective refractory period （ERP） were compared between the two groups. Results：There was no difference in AH interval,AVN antegrade and retrograde Wenckbach＇ s block points（ms） in the patients before and after RFCA （ P 〉 0. 05 ）. The fast pathway antegrade ERP was shortened in Group A （ P 〈 0. 05 ） but not changed in Group B （ P 〉 0.05 ） after RFCA. The slow pathway antegrade ERP was extended in Group B （ P 〈 0. 05 ）. Conclusion：The shortened fast pathway antegrade ERP was associated with the residual slow pathway. The ablation by slow pathway only enfluences AVN antegrade conduction.