肥胖儿童心脏结构和功能特征

摘要

目的:评价肥胖儿童心脏结构和功能的特点,旨在评估心脏早期改变的风险性和不良后果.方法:将北京市5所小学的1034名8～9岁儿童(男n=514,女n=520)依照体脂率(BF％)分类标准,男、女各分成体脂率正常组(男n=206,女n=336)、超重组(男n=94,女n=80)、肥胖组(男n=214,女n=104).对所有受试者进行超声心动图检查,并分性别比较各组心脏结构和功能指标.结果:(1)与体重正常儿童相比,肥胖儿童左心室舒张末期内径(LVIDd)、舒张末期左室后壁厚度(LVPWd)、左心室舒张末期容积(EDV)、左心室质量(LVM)、左心室质量指数(LVMI)、每搏量(SV)、心输出量(CO)均非常显著性增加(P＜0.01),但射血分数(EF)、短轴缩短率(FS)无统计学差异(P＞0.05).(2)儿童BF％与主动脉根部内径(AOD)、舒张末期室间隔厚度(IVSd)、LVIDd、舒张末期左室后壁厚度(LVPWd)、EDV、LVM、LVMI、CO、SV呈正相关(P＜0.01).(3) 8～9岁超重肥胖儿童心脏向心性肥厚的比例为6.1％.与左室正常构型儿童相比,心脏向心性肥厚儿童形态指标BF、BF％、BMI和心脏指标LVM、LVMI、相对室壁厚度(RWT)非常显著性增加(P＜0.01),CO显著性增加(P＜0.05),SV显著性减小(P＜0.05).结论:以体脂率作为肥胖筛查指标发现,8～9岁肥胖儿童发生心脏重构和功能改变,包括左心室扩大、室壁增厚、左室质量增加、左室肥厚及每搏量、心输出量增加,且随肥胖程度加重,向心性肥厚发生率增高.%Objective To observe the cardiac structure and function of obese children,so as to evaluate the risk of early pathological changes and severe consequences.Methods One thousand and thirty-four children (aged between 8 and 9,of 520 females) from 5 primary schools in Beijing were recruited and randomly divided into 2 normal groups (206 males and 336 females),2 overweight groups (94 males and 80 females) and 2 obesity groups (214 males and 104 females) according to the sex and body fat percentage (BF％.The cardiac structure and function were measured using echocardiography.Results (1) Compared with the normal groups,significant increase was observed in the left ventricular internal diameter at end-diastole (LVIDd),left ventricular posterior wall dimensions (LVPWd),left ventricular end-diastolic volume (EDV),left ventricular mass (LVM),left ventricular mass index (LVMI),stroke volume (SV) and cardiac output (CO) in the obesity groups (P＜0.01).However,no significant differences were observed between the 2 groups in the ejection fraction (EF) and fractional shortening (FS) (P＞0.05).(2) BF％ was positively correlated with the aortic root dimension,IVSd,LVIDd,LVPWd,EDV,LVM,LVMI,CO and SV (P＜0.01).(3) The prevalence of concentric hypertrophy was 6.1％ among the overweight and obese children aged between 8 and 9.Compared with the normal children,significant increase was found in their BF,BF％,body mass index,LVM,LVMI and RWT,but significant decrease in SV (P＜0.05).Conclusions Screening with BF％,the overweight and obese children between 8 and 9 years old have showed obvious changes in their cardiac structure and function,including higher left ventricular internal diameter at end-diastole,thicker left ventricular wall as well as bigger left ventricular end-diastolic volume,left ventricular mass,left ventricular mass index,stroke volume and cardiac output.Meanwhile,the prevalence of concentric hypertrophy increased with the increase of body fat percentage.