经CT定位不同部位间隔起搏的心电图特征分析

目的 探讨不同间隔部位起搏的体表心电图特征.方法 观察31例永久性心脏起搏器间隔起搏患者体表心电图特征,使用64排双源CT精确定位起搏导线在间隔部的具体位置,比较不同位置间隔起搏的心电图参数变化.结果 ①仅根据X线植入的起搏导线,起搏导线误置于前壁的占12.9%.②前壁起搏的QRS间期（148±19）ms,宽于高位间隔起搏QRS间期（118±24）ms（P＜0.05）.③中位间隔起搏QRS波群移行6.00±0.76,晚于高位间隔（4.13±1.56）和低位间隔（3.75±2.99）（均P＜0.05）.④高位间隔起搏RIII（1.11±0.70）mV,大于低位间隔起搏RⅢ（0.038±0.075）mV（P＜0.05）.⑤高位间隔起搏（46.7%）及中位间隔起搏（37.3%）I出现q波或QS的比例有多于前壁起搏的趋势.结论经CT定位不同部位间隔起搏的体表心电图存在明显不同,一些参数有助于判断导线位置.

Electrocardiographic Characteristics of Septal Pacing at Different Sites Confirmed by Computed Tomography

Objective To investigate electrocardiographic （ECG） characteristics of septal pacing at different sites. Methods The exact position of the septal pacing lead was confirmed by computed tomography retrospectively in 31 patients implanted with a pacemaker. ECG characteristics of septal pacing at different sites were analyzed. Results Up to 12.9% of the pacing leads were actually located at the anterior wall instead of the septum. The QRS duration of anterior wall pacing was greater than that of high-septal pacing （ 148 ± 19ms vs. 118 ± 24ms, P〈0.05 ）. QRS transition was significantly later during mid-septat pacing than during high-septal and Iow-septal pacing （6.00±0.76 vs. 4.13 ± 1.56 and 3.75 ± 2.99, P〈0.05）. R wave amplitude of high-septal pacing was significantly greater than that of Iow-septal pacing in lead III （1.11 ± 0.70mV vs. 0.038 ± 0.075mV,P〈0.01）. A q-wave or QS wave in lead I was seen in 46.7% high-septal pacing, 37.3% mid-septal pacing and none of anterior wall pacing. Conclusion Surface ECG patterns vary with septal pacing sites obviously. Some of ECG parameters may be used to estimate lead position.