Vaksmann G, Gutierrez R, Duhamel A, Nelken B, Francart C, Kouakam C, Mazingue F, Rey C
Department of Pediatric Cardiology, Cardiologic Hospital, F59037, Lille, France.
Pediatr Cardiol. 2001 Nov-Dec;22(6):494-8. doi: 10.1007/s002460010282. Epub 2001 Dec 4.
The aim of the present study was to determine if signal-averaged ECG of patients with anthracycline-induced left ventricular dysfunction could differentiate between patients with anthracycline-induced cardiotoxicity and those without. Sixteen children with anthracycline-induced cardiomyopathy, aged 6.5 to 15.5 years (anthracycline dose = 198-737 mg/m2), and 31 patients aged 5.0 to 16.7 years, who received anthracyclines without evidence of left ventricular dysfunction (anthracycline dose = 120-517 mg/m2), were studied with signal averaged ECG. The two groups were comparable in age, body surface area, and time since completion of chemotherapy. Signal averaged ECG parameters of the patients were compared with data obtained from 530 healthy children. These parameters were converted to z-scores to account for growth-related changes in signal averaged ECG recordings. Z-scores for filtered QRS duration and low amplitude terminal signal < 40 microV were significantly lower (p = 0.002 and p = 0.015, respectively), and Z-score for root mean square voltage of the last -30 ms of filtered QRS tended to be higher (p = 0.06) in patients with left ventricular dysfunction. Filtered QRS duration lower than -1.5 SD was found in 4 of 16 patients with left ventricular dysfunction and in only 1 of 31 patients without (p < 0.05) yielding a sensitivity of 25% and a specificity of 97% to detect left ventricular dysfunction. Only 1 patient had late potentials; his left ventricular function was normal. Left ventricular mass index tended to be lower in patients with left ventricular dysfunction (p = 0.07), whereas left ventricular diastolic diameter was similar in the two groups. The mechanism that accounted for the difference in signal averaged-ECG between the two groups of patients could be linked with the decrease in left ventricular mass in patients with left ventricular dysfunction. In conclusion, children with left ventricular dysfunction following anthracycline therapy have a SA ECG different from those without left ventricular dysfunction, which is mainly characterized by a lower filtered QRS duration. A prospective study is needed in order to determine if this modification of SA ECG recordings precedes alteration of left ventricular function, and, therefore, if it could help in early detection of cardiac toxicity of anthracyclines.
本研究的目的是确定蒽环类药物引起的左心室功能障碍患者的信号平均心电图能否区分蒽环类药物引起的心脏毒性患者和未发生心脏毒性的患者。对16名年龄在6.5至15.5岁（蒽环类药物剂量 = 198 - 737 mg/m²）的蒽环类药物引起的心肌病患儿以及31名年龄在5.0至16.7岁、接受蒽环类药物治疗但无左心室功能障碍证据（蒽环类药物剂量 = 120 - 517 mg/m²）的患者进行了信号平均心电图研究。两组在年龄、体表面积和化疗结束后的时间方面具有可比性。将患者的信号平均心电图参数与从530名健康儿童获得的数据进行比较。这些参数被转换为z分数，以考虑信号平均心电图记录中与生长相关的变化。左心室功能障碍患者的滤波QRS波时限和低振幅终末信号<40微伏的z分数显著更低（分别为p = 0.002和p = 0.015），并且滤波QRS波最后30毫秒的均方根电压的z分数倾向于更高（p = 0.06）。在16名左心室功能障碍患者中有4名发现滤波QRS波时限低于 - 1.5标准差，而在31名无左心室功能障碍的患者中只有1名（p < 0.05），检测左心室功能障碍的敏感性为25%，特异性为97%。只有1名患者有晚电位；他的左心室功能正常。左心室功能障碍患者的左心室质量指数倾向于更低（p = 0.07），而两组的左心室舒张直径相似。两组患者信号平均心电图差异的机制可能与左心室功能障碍患者左心室质量的降低有关。总之，蒽环类药物治疗后出现左心室功能障碍的儿童的信号平均心电图与无左心室功能障碍的儿童不同，其主要特征是滤波QRS波时限更低。需要进行一项前瞻性研究，以确定这种信号平均心电图记录的改变是否先于左心室功能的改变，以及因此它是否有助于早期检测蒽环类药物的心脏毒性。
