对房室结双径路不同电生理传导现象的本质探讨

Essence of different conduct appearence in patients with dual atrioventricular nodal pathways

目的 :为探讨房室结双径路不同电生理传导现象的本质。 方法 :根据房室结双径路的不同电生理传导现象 ,将房室结折返性心动过速分为曲线平滑型 (A组 )和曲线中断型 (B组 ) ,并在射频消融慢径路前后对各项电生理参数进行比较分析 ,以观察房室结功能曲线的变化。 结果 :A组消融慢径后 ,房室结有效不应期从 (2 6 8± 36 ) ms增至 (336± 32 ) ms(P<0 .0 1) ,心房起搏时最长 AH从 (2 6 6± 2 4) m s减至 (196± 6 6 ) ms(P<0 .0 1) ;B组消融后 ,房室结有效不应期从 (2 79± 42 ) m s增至 (34 6± 48) m s(P<0 .0 1) ,心房起搏时最长 AH从 (2 91± 32 ) m s减至 (192±5 4) ms(P<0 .0 1)。 结论 :房室结折返性心动过速平滑曲线的实质也是由快径和慢径两种成分组成 ,消融慢径后 ,可使曲线的“尾部”消失 ,这对射频消融慢径终点的判断具有重要的临床意义。

Obsjectives:The report is intented to discuss the essence of different conduct appearence in patients with dual atrioventricular nodal pathways. Methods:Before and after the ablation of slow pathway,10 patients with AV node reentrent tachycardia(AVNRT) and smooth AV node function curves(group A) were compared with 10 patients with AVNRT and discontinuous AV node function curves(group B). Results:In group A,the effective refractory period of the AV node(ERPavn) increased(268±36 versus 336±32ms, P <0.01) and the maxmium AH interval(AHmax) decreased(266±24 versus 196±66ms, P <0.01) after ablation.In group B,ERPavn increased(279±42 versus 346±48ms, P <0.01) and AHmax decreased(291±32 versus 192±54ms, P <0.01) after ablation. Conclusions:This study suggests that the smooth AV node function curve consists of two distinct components representing both fast and slow AV node pathways.It is of great importance in determining the end point of radiofrequency cathete ablation in AVNRT.