显性房室旁道射频消融术后QRS波群高频成分的变化及意义

探讨房室旁道电位的电物理特性 ,同时借助房室旁道这一除极顺序异常的天然模型 ,印证心室激动传导异常产生高频成分这一机制。选择显性房室旁道伴房室折返性心动过速患者 4 0例 ,采用信号平均技术及多采样率线性小波转换技术 ,对射频消融前、后体表心电图窦性心律时 QRS波群全程及起始部 4 0 ms进行三维频谱分析 ,观察高频能量 (E1 )、甚高频能量 (E2 )、频谱的最高上限频率 (Fmax)及 QRS时限 (QRSI)等参数的变化。结果 :QRS波群全程 E1 、E2 、Fmax射频消融前后相比无统计学差异。而 QRSI射频消融前后相比差异显著 (12 3± 15 msvs86± 9ms,P<0 .0 0 1)。QRS波群起始部 4 0 ms的 E1 、E2 、Fmax术前分别为 1.2 3 7± 0 .4 5 9,0 .74 8± 0 .2 5 3 ,3 66± 4 9Hz;术后分别为 0 .73 2± 0 .2 95 ,0 .3 64± 0 .161,3 0 9± 3 8Hz,与术前相比差异显著 (P均 <0 .0 1)。结论 : 旁道激动心室是高频成分产生的一种机制 , 冲动沿旁道下传 ,心室激动时间延长 , 心室预激波是一种含高频成分和高频能量较多的电信号 ,其频率可达 4 0 0 Hz以上 ,提示在心内电生理标测时采用较高频率的滤波带 ,可能使旁道电位显示更清晰。

The Changes and Its Meaning of High Frequency Components in QRS Complexes of Radiofrequency Ablated Overt Atrioventricular Accessary Pathways

In order to study the electrophysical characteristics of overt atrioventricular accessary pathway (AP) potential and to affirm the mechanism that abnormal ventricular activation and conduction result in high frequency components.Methods:Electrocardiographic QRS complexes of 40 patients with single overt AP were analysed before and after radiofrequency current ablation by three dimensional spectrum based on multiple sample rate linear wavelet transformation and signal averaged techniques.Results:there werent significantly statistical difference between before and after ablation in tatol QRS complexes E 1,E 2 and F max (all P >0.05);however QRSI obviously shortened after ablation (86±9 ms vs 123±15 ms, P <0.001).Analysis for initial 40 ms of QRS complexes showed that E 1,E 2,and F max before ablation were 1.237±0.459,0.748±0.253,366±49 Hz;after ablation 0.732±0.295,0.364±0.161,309±38 Hz,The later was obviously smaller than the former (all P <0.01) .Conclusion:① Abnormal ventricular depolarization based on AP is a mechanism resulting in high frequency components.② When the pules propagate along AP,ventricular activation time prolong obviously.③Ventricular preexcitation wave is a kind of electrocardiographic signal which contains more high frequency components.