目的：探讨小儿扩张型心肌病（DCM）的心电图特点及DCM并心律失常的相关因素。方法：总结68例1998年1月至 2010年3月住院的 DCM 患儿的临床资料，根据有无心律失常及严重程度分为3组：严重心律失常组(42例)，非严重心律失常组(20例)，无心律失常组(6例)，比较各组的左心室舒张末期内径（LVED）、左心室射血分数（LVEF）及短轴缩短率（LVFS）。结果：68例DCM患儿心电图均存在异常，以窦性心动过速（91%）和异位搏动（86%）最常见。严重心律失常组LVED（74±6 mm）大于非严重心律失常组（65±4 mm）和无心律失常组（61±3 mm）；非严重心律失常组LVED亦大于无心律失常组,各组间差异有统计学意义（P<0.05）。严重心律失常组LVEF、LVFS 分别是(30±11)%、（22±4)%，低于非严重心律失常组［（37±12）%、（28±5）%］和无心律失常组［（45±9）%、（34±7）%］； 非严重心律失常组LVEF、LVFS亦低于无心律失常组，各组间差异有统计学意义（P<0.05）。结论：DCM患儿心电图异常以窦性心动过速和异位搏动最常见；心律失常是DCM的主要临床表现之一；心律失常的发生与左心室大小、心功能关系密切。

OBJECTIVE: To study the ECG features in children with dilated cardiomyopathy (DCM), and related factors for the occurrence of arrhythmia secondary to DCM. METHODS: Data from 68 children with DCM from January 1998 to March 2010 were studied. The children were classified into three groups: severe arrhythmia (n=42), non-severe arrhythmia (n=20) and non-arrhythmia (n=6). Left ventricular end diastolic diameter (LVED), left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) were compared. RESULTS: Abnormal ECG results were found in all of the 68 children with DCM. Sinus tachycardia (91%) and ectopic pulsatile (86%) were common. LVED in the severe arrhythmia group (74±6 mm) was greater than that in the non-severe arrhythmia group (65±4 mm; P<0.05) and non-arrhythmia group (61±3 mm; P<0.05). LVED in the non-severe arrhythmia group was also greater than that in the non-arrhythmia group (P<0.05). LVEF and LVFS in the severe arrhythmia group were (30±11)% and (22±4)%, respectively, which were lower than those in the non-severe arrhythmia group［(37±12)% and (28±5)%, respectively］and non-arrhythmia group［(45±9)% and (34±7)%, respectively］(P<0.05). There were also significant differences in the LVEF and LVFS between the non-severe arrhythmia and non-arrhythmia groups (P<0.05). CONCLUSIONS: The common abnormal ECG findings are sinus tachycardia and ectopic pulsatile in children with DCM. Arrhythmia is one of the main clinical manifestations of DCM. The occurrence of arrhythmia is associated with the left ventricular size and heart function.