儿童室性期前收缩QT间期离散度和心率变异性的研究

摘要

Objective To investigate the changes of QT dispersion and heart rate variability in children with ventricular contraction. Methods 50 healthy children who came for medical examinations at Chengdu Women′s and Children′s Central Hospital from January 2012 to January 2014 were selected as control group. 147 children with ventricular contraction admitted in Pediatric Intracardiac Department of Chengdu Women′s and Children′s Central Hospital from January 2012 to January 2014 were divided them into Benign Group (LownⅠ&LownⅡ) and Malignant Group(LownⅢ, LownⅣA, LownⅣB&LownⅤ) according to the results of Lown classification. Benign Group contained 90 cases while Malignant Group contained 57 cases. Difference in QT dispersion and indices of heart rate variability of the three groups were compared. Results There were no statistically differences between control group and benign group in QT dispersion (P > 0.05). QT dispersion of malignant group was much longer than that of control group and the differences had statistically meaning(P<0.001). SDNN(standard deviation of NN intervals) , SDANN (standard deviation of the averages of RR intervals ), SDNN index (index of standard deviation of the averages of NN intervals), rMSSD(root mean square of successive differences) and PNN50(percentage of successive normal sinus RR intervals>50 ms) of malignant group was much shorter than that of control group and benign group and the differences had statistically meaning (P< 0.01). SDNN, SDANN and SDNN index of benign group was shorter than that of control group and the differences had statistically meaning (P<0.05). Conclusions Heart rate variability of children with malignant ventricular contraction becomes significantly shorter and QT dispersion becomes significantly longer. Detection of QT dispersion and heart rate variability can effectively predict the risky degree of ventricular contraction in children.%目的：研究儿童室性期前收缩与QT间期离散度的变化以及心率变异性的关系。方法：选取2012年1月到2014年1月至成都市妇女儿童中心医院进行体检的50例正常儿童作为对照组，选取成都市妇女儿童中心医院小儿心内科于2012年1月到2014年1月收治的147例室性期前收缩患儿作为临床研究对象，并根据Lown分级结果将这147例患儿分为良性组（LownⅠ、Ⅱ）90例和恶性组（LownⅢ、ⅣA、ⅣB、V级）57例，对比3组患儿的QT间期离散度和心率变异性的各项指标。结果：（1）良性组患儿与对照组儿童的QT间期离散度无统计学差异（P＞0．05），恶性组患儿的QT间期离散度要明显高于功能组与对照组，差异具有显著的统计学意义（P＜0．001）；（2）根据试验结果可知，恶性组患儿的NN间期标准差（SDNN）、NN间期均值标准差（SDANN）、NN间期标准差指数（SDNN index）、相邻NN间期差值均方根（rMSSD）、相邻NN间期差值超过50ms心搏数百分率（PNN50）等数据均要明显低于良性组和对照组，差异具有统计学意义（P＜0．01）；良性组患儿的SDNN、SDANN、SDNN index要明显低于对照组，差异具有统计学意义（P＜0．05）。结论：恶性室性期前收缩的患儿心率变异性显著降低，QT间期离散度显著增高，QT间期离散度以及心率变异性检测可以有效地预测儿童室性期前收缩的危险程度。