B型预激后间隔旁道体表心电图定位及鉴别诊断

Differential diagnosis and localization for posterior septal atrioventricular accessory pathway in type B Wolff-Parkinson-White (WPW) syndrome on surface electrocardiogram(ECG)

目的 探讨B型预激综合征在左右后间隔旁道的位置与体表心电图特征性改变的相关关系。方法 以80例B型预激综合征射频消融的结果作对照,寻找体表心电图的特征性改变与左右后间隔旁道位置关系,确定体表心电图左右后间隔旁道的鉴别诊断标准,并计算其鉴别诊断的敏感性、特异度和准确率。结果 结果显示体表心电图的11项特征变化与B型预激左右后间隔旁道定位鉴别诊断有关,即V_1导联中P-R间期长短、QRS波形态、δ波方向及S波的深度;δ波及QRS波的额面电轴及二者差值;Ⅲ导联R/S波比值;胸前导联R/S>1的转折点;下壁导联中(Ⅱ,ⅢavF)负性δ波的数量;P_(v1)-P_E间距。根据以上11项特点对术前80例B型预激重新定位,其鉴别诊断敏感性、特异度及准确率在右后间隔旁道分别是88.2％,83.3％和77.5％,而左后间隔是83.3％,88.2％,87.5％。结论 B型预激旁道绝大部分位于右后间隔旁道,但也不排除左后间隔旁道,尤其是左后旁道预激不完全时可出现B型预激改变,上述体表心电图的11项特征有助于二者鉴别诊断。

Objective To explore correlation between posterior septal accessory pathway site of type WPW and characteristic change of surface ECG. Methods The results of radiofrequency catheter ablation(RFCA)of 80 cases of type B WPW were regarded as controls; characteristic changes of surface ECG were detected and posterior septal accessory pathway site were localized. The differential diagosis criteria for left and right posterior septal accessory pathway were es-tabished accordingly. The sensistvity, specifivity and accuracy were calculated. Results The result showed that the following eleven characteristic changes of surface ECG were related with the differential diagnosis and localization of left and right posterior septal accessory: P-R interval, QRS wave shape! delta wave polarity and the depth of S wave in V1 lead; delta wave and QRS wave axes in the frontal plane; the angle differnce between QRS wave and delta wave axes ; the R/S ratio in Ⅲ lead; R/S>1 ratio in precordial leads; the number of negtive delta waves in inferoior wall leads( Ⅱ , Ⅲ ,avF)and PVI-PE interval. According to the above eleven characteristcs of surface ECG, 80 cases of B type were relocalized preopera-tively and its sesitivity, specificity and accuracy were found to be 88. 2%, 83. 3% and 77. 5% in the right posterior septal accessory pathways respectively, while they were 83. 3% , 88. 2% and 87. 5 in the left. Conclusions Although most of accessory pathways in type B WPW syndrome were located on the righ posterior septal, but it could not be ruled out that they were located in the left, especially when the left posteror septal accessory pathway was partially excited, it looked like type B WPW syndrome. The eleven characteristic changes of surface ECG were usefull to differentially diagnose the two types of accessory pathways.