应用24 h动态心电图分析不同年龄段心肌炎患儿心率变异性的特点

Characteristics of heart rate variability monitored by 24-hour ambulatory electrocardiogram in children with myocarditis of different ages

目的应用24 h动态心电图分析不同年龄段心肌炎患儿心率变异性(HRV)的特点。方法回顾性抽取2022年9月至2023年12月河南省儿童医院郑州儿童医院收治的心肌炎患儿68例,按照年龄段分为低龄组(24例,≤4岁)、中龄组(21例,5~9岁)、高龄组(23例,10~12岁)。另抽取同期健康体检儿童68例,其中≤4岁24例(低龄对照组),5~9岁21例(中龄对照组)和10~12岁23例(高龄对照组)。所有儿童实施24 h动态心电图检查。比较低龄组与低龄对照组、中龄组与中龄对照组、高龄组与高龄对照组HRV指标[正常窦性心律RR间期的标准差(SDNN)、每5 min RR间期标准差(sDANN)、低频功率(LF)、高频功率(HF)、相邻RR间期差值>50 ms的心搏个数占RR间期总数的百分比(PNN50)、24 h全程相邻RR间期差值的均方根(rMSSD)]水平,分析不同年龄段心肌炎患儿的HRV特点。结果三组(低龄组、中龄组、高龄组)SDNN、sDANN、LF、HF、PNN50、rMSSD低于相应对照组(低龄对照组、中龄对照组、高龄对照组),P<0.05。中龄组和高龄组SDNN、sDANN、LF、HF、PNN50、rMSSD高于低龄组(P<0.05),高龄组SDNN、sDANN、LF、HF、PNN50、rMSSD高于中龄组(P<0.05)。结论心肌炎患儿的HRV水平明显低于健康儿童,且年龄越高者HRV水平越高,24 h动态心电图能显示心肌炎患儿HRV指标,可为后续开展治疗提供参考依据。

Objective To investigate the characteristics and value of heart rate variability(HRV)evaluated by 24-hour ambulatory electrocardiogram in children with myocarditis of different ages.Methods A total of 68 children with myocarditis admitted to Henan Children’s Hospital Zhengzhou Children’s Hospital from September 2022 to December 2023 were retrospectively selected,and they were divided into the younger age group(24 cases,≤4 years old),the middle-aged group(21 cases,5 to 9 years old),and the older age group(23 cases,10 to 12 years old).In addition,another 68 children who underwent physical examination during the same period were selected,including 24 cases≤4 years old(young control group),21 cases of 5 to 9 years old(middle-aged control group)and 23 cases of 10 to 12 years old(elderly control group).All children underwent 24-hour ambulatory electrocardiogram examination.The levels of HRV indexes were compared between the younger age group and the young control group,between the middle-aged group and the middle-aged control group,and between the older age group and the elderly control group,such as standard deviation of all normal to normal R-R(NN)intervals(SDNN),standard deviation of the averages of normal-to-normal intervals in all 5-minute segments of the entire recording(sDANN),low frequency power(LF),high frequency power(HF),percentage of intervals>50 ms different from preceding interval(PNN50),and the square root of the mean of the squares of successive normal to NN interval differences(rMSSD).The HRV characteristics of children with myocarditis of different ages were analyzed.Results The SDNN,sDANN,LF,HF,PNN50 and rMSSD of the younger age group,middle-aged group and the older age group were lower than those of the corresponding control groups(young control group,middle-aged control group,and elderly control group),P<0.05.The SDNN,sDANN,LF,HF,PNN50 and rMSSD of the middle-aged group and the older age group were higher than those of the younger age group(P<0.05);while the SDNN,sDANN,LF,HF,PNN50 and rMSSD of the older age group were higher than those of the middle-aged group(P<0.05).Conclusions The HRV indexes of children with myocarditis are significantly lower than those of healthy children.Moreover,the older the patients,the higher the HRV level.And the 24-ambulatory electrocardiogram can show the HRV indicators of children with myocarditis,which can provide a reference for subsequent treatment.