体重指数对中国成年男性左心结构和功能影响的心血管MRI研究

目的应用心血管磁共振(cardiovascular magnetic resonance,CMR)评价体重指数(body mass index,BMI)对中国成年男性左心结构和功能的影响。方法选取2010年10月~2018年3月行CMR检查的男性体检者共420例,年龄30~50岁,按体重指数(BMI)分为三组,正常体重组(<24 kg/m²)164例、超重组(24.0~27.9 kg/m²)190例和肥胖组(≥28.0 kg/m²)66例。应用1.5T Siemens Magnetom Essenza和GE磁共振扫描仪进行CMR检查,应用CVI⁴²(v5.6.2,Canada)软件包进行心脏结构及功能参数的测量,将乳头肌纳入心肌质量,不计入心室容积;心室容积包含心室流出道,逐层勾画出左室心内膜、心外膜轮廓后计算得出以下参数:左心室舒张末期容积(EDV)、收缩末期容积(ESV)、射血分数(EF)、每搏输出量(SV)、心输出量(CO)、心肌质量(LVM)及经体表面积(BSA)校正的值:EDVI=EDV/BSA、ESVI=ESV/BSA、LVMI=LVM/BSA,左心室心肌质量容积比LVM/EDV。结果CO、LVM、LVM/EDV与BMI呈正相关(P<0.05)。与正常体重组比较,超重组及肥胖组EDV、SV显著增加,超重组EF较正常体重组增大(P<0.05)。经BSA校正,超重组ESVI、LVMI及肥胖组EDVI、ESVI、LVMI均与正常体重组差异有统计学意义(P<0.05),而超重与肥胖组两组间及ESV各组间差异无统计学意义(P=0.42)。结论BMI增加可使EDV、CO、SV、EF及LVM改变,且超重未达肥胖时,即可引起左心室重构、影响左心收缩功能;BSA可校正部分由BMI增加导致的左心结构功能参数改变的差异。

Effects of body mass index on left ventricular structure and function in Chinese adult men: a cardiovascular magnetic resonance imaging study

Objective To explore the evaluation of body mass index(BMI)on left ventricular structure and function in Chinese adult men by Cardiovascular Magnetic Resonance(CMR).Methods 164 normal-weight(BMI<24.0,age 41.2±5.5 years),190 overweight(24.0 BMI≤27.9,age 41.5±5.8 years)and 166 obese(≥28.0,age 40.4±6.3 years),healthy male adults who underwent CMR imaging retrospectively analyzed.Papillary muscle was included in the myocardial mass and not included in the ventricular volume;the ventricular volume included the ventricular outflow tract,and the left ventricular(LV)endocardium and epicardium were delineated layer by layer.Investigate the differences in of left ventricular(LV)end-diastolic volume(EDV),end-systolic volume(ESV),ejection fraction(EF),stroke volumes(SV),cardiac output(CO),LV mass(LVM),LVM/EDV and the values corrected by body surface area(BSA)among groups.Include EDVI,ESVI,LVMI.Results CO,LVM,LVM/EDV were positively correlated with BMI(P<0.05).Compared with normal weight group,EDV and SV of overweight and obesity group were significantly increased,and EF of overweight group was larger than that of normal weight group(all P<0.05).After BSA correction,ESVI,LVMI of overweight group and obesity group were significantly different from those of normal weight group(P<0.05),but there was no significant difference between overweight and obesity groups and ESV groups(P=0.42).Conclusion LV concentric remodeling is significant in healthy obese,even overweight.BSA can correct the difference of structural and functional parameters of left heart caused by the increase of BMI.