Objective: To study the association of T-wave amplitude on electrocardiogram (ECG) with left ventricular ejection fraction (LVEF) in children with dilated cardiomyopathy.
Methods: A retrospective analysis was performed for the clinical data of 44 children who were diagnosed with dilated cardiomyopathy from May 2009 to June 2018. According to LVEF, they were divided into two groups: LVEF ≥50% group (n=26) and LVEF <50% group (n=18). After treatment, 25 children were followed up for 3-42 months (mean 14±9 months). The Guangdong Zhongshan SR-1000A ECG Automatic Analyzer was used to obtain the 12-lead body surface ECG results in the supine position. T-wave amplitude on ECG was evaluated by software and manual measurement.
Results: Compared with the LVEF ≥50% group, the LVEF <50% group had a significant reduction in the T-wave amplitude in leads II, V4, V5 and V6 (P<0.05). The increased-LVEF group (an increase in LVEF > 5% after treatment) had a significant increase in the T-wave amplitude in leads aVR, V5, and V6 after treatment (P<0.05), while the unchanged-LVEF group (an increase in LVEF ≤ 5% after treatment) had a significant reduction in the T-wave amplitude in lead aVR after treatment (P<0.05). The receiver operating characteristic curve analysis showed that the T-wave amplitude in leads II, V4, V5 and V6 had a certain value in predicting LVEF <50% in children with dilated cardiomyopathy (P<0.05). A combination of T-wave amplitude of ≤0.20 mV in lead II, ≤0.40 mV in lead V4, and ≤0.30 mV in leads V5 and V6 had a sensitivity of 88.2% and specificity of 76.0% in the predication of LVEF <50% in children with dilated cardiomyopathy.
Conclusions: T-wave amplitude on ECG can be used as the indexes for the evaluation of the left ventricular systolic function in children with dilated cardiomyopathy.
目的: 探讨心电图T波振幅与儿童扩张性心肌病左室射血分数（LVEF）的关系。
方法: 回顾性分析2009年5月至2018年6月诊断为扩张性心肌病的44例儿童的临床资料。根据LVEF分为LVEF ≥ 50%组（n=26）和LVEF < 50%组（n=18），且对治疗后25例进行3~42个月（平均14±9个月）的随访。采用广东中山SR-1000A心电综合自动分析仪描记仰卧位12导联体表心电图，程序自动分析结合人工干预测量12导联心电图T波振幅。
结果: （1）T波振幅比较：LVEF < 50%组较LVEF ≥ 50%组Ⅱ、V4、V5、V6导联T波振幅明显降低（P < 0.05）。LVEF增高组（治疗后较治疗前LVEF增加>5%）治疗后aVR、V5、V6导联T波振幅明显增高（P < 0.05）；LVEF不变组（治疗后较治疗前LVEF增加≤ 5%）治疗后aVR导联T波振幅明显降低（P < 0.05）。（2）受试者工作特征曲线评价：Ⅱ、V4、V5、V6导联T波振幅对扩张性心肌病患儿LVEF < 50%具有预测价值（P < 0.05）。当同时出现Ⅱ导联T波振幅≤ 0.20 mV、V4导联T波振幅≤ 0.40 mV、V5导联T波振幅≤ 0.3 mV、V6导联T波振幅≤ 0.30 mV时，预测扩张性心肌病患儿LVEF < 50%的灵敏度为88.2%，特异度为76.0%。
结论: 心电图T波振幅可作为评估儿童扩张性心肌病左室收缩功能的指标。