Development of quantitative evaluation of the repolarization changes in myocardial damage in children and an analysis of their origin

我们通过QRST等积分图的发现，对儿童年龄组心肌损伤引起的复极异常进行了定量评估。此外，我们还通过激活恢复间隔（ARI）的分布研究了异常的机制，ARI声称与局部动作电位持续时间相关。将100例无心脏病的正常儿童的QRST等积分图与日本循环学会特别工作组委员会收集的年龄匹配的正常平均QRST等积分图进行比较，并计算全身体表导联的相关系数（R值）。QRST等积分图除前胸阳性区有轻微变化外，其他年龄组的QRST等积分图结果相似。正常组R值平均值为0.92 ~ 0.88。在对心肌损伤患者R值的系列评价中，心肌损伤加重时，其QRST等积分图R值显著降低，心肌损伤消失或恢复时，R值归一化。先天性冠状动脉畸形和蒽环类心肌损伤患儿的R值定量评价也是可行的。超声心动图R值较好地反映了充血性心力衰竭或左室功能不全的临床症状。结果表明，QRST等积分图R值定量评价心肌损伤复极异常具有临床价值。通过ARI分布的进一步研究发现，与正常儿童相比，患者在受损心肌区域存在延长的ARI。下位心肌梗死患者，延长的ARI值广泛分布在下胸部区域。另一名前路梗死患者在前胸表现出延长的ari值。提示APD在损伤心肌中延长，可能与患者心电图复极变化有关。少

We have developed a quantitative evaluation of the repolarization abnormalities due to myocardial damage in pediatric age group by findings of QRST isointegral maps. Furthermore, we also investigated the mechanism of the abnormalities by the distribution of activation recovery interval (ARI), which claimed to correlate to local action potential duration.QRST isointegral maps of 100 normal children without heart diseases were compared to age matched normal averaged QRST isointegral maps-collected by the Task Force Committee of Japanese Circulation Society and correlation coefficient from the whole body surface leads were calculated (R value). QRST isointegral map findings were resembled at any age groups except slight changes in positive area on anterior chest. R values of normal group were varied from 0.92 to 0.88 in their mean value. In serial evaluations of R values in patients with myocardial damage, the R -values of their QRST isointegral maps were significantly decreased at the pr … More esence of myocardial damage, and they normalized at absence or recovery of myocardial damage. The quantitative evaluation by R values were also possible in children with congenital coronary malformations and anthracycline myocardial damage. R values were well reflect the clinical symptoms of congestive heart failure or LV dysfunction in echocardiography. The results demonstrated that clinical usefulness of the quantitative evaluation of repolarization abnormalities of myocardial damage by R values of QRST isointegral maps.Further study by the distributions of ARI disclosed the presence of the prolonged ARI on the area of damaged myocardium in patients compared to normal children. A patient with inferior myocardial infarction, prolonged ARI values are widely distributed on the lower chest area. Another patient with anterior infarction showed prolonged-ARI values on anterior chest. The findings suggest that APD is prolonged in injured myocardium, and it may responsive for the repolarization changes of electrocardiogram of the patients. Less