基于CT成像分析正常高值血压伴腹型肥胖者的升主动脉弹性特点

Analysis of Ascending Aorta Elasticity in Patients with High-Normal Blood Pressure and Abdominal Obesity Based on CT Imaging

目的利用低剂量CT冠状动脉成像联合CT脂肪定量技术分析正常高值血压伴腹型肥胖者的升主动脉弹性特点。方法搜集本院2015年1月至12月40岁以上职工体检者173例,所有均行320排低剂量CT冠状动脉成像及腹部CT检查。根据内脏脂肪体积(VAT)及血压将研究对象分为四组:正常高值血压伴腹型肥胖组45例(A组)、正常高值血压体重正常组41例(B组)、理想血压腹型肥胖组36例(C组)、理想血压体重正常组51例(正常对照组)。所有入选者CT数据均利用Vitrea FX后处理软件半自动测量并计算升主动脉压力-应变弹性系数(Ep)及腹部VAT、腹部皮下脂肪体积(SAT)。记录所有患者的CT容积剂量指数(CTDIvol)、剂量长度乘积(DLP)。结果A组受试者的升主动脉Ep(287.15±26.73)高于正常对照组(P<0.01)及B组和C组(P<0.01);B组受试者的升主动脉Ep(236.73±23.67)和C组(242.61±23.29)高于正常对照组(P<0.01);B组受试者的升主动脉Ep与C组无统计学差异(P>0.05)。多因素协方差分析结果显示VAT(F=2.284,P=0.02)和收缩压(F=2.195,P=0.028)分别对Ep有显著影响,并且存在交互协同效应。结论正常高值血压伴腹型肥胖者已经存在升主动脉弹性功能的下降,VAT增加和收缩压升高对升主动脉弹性功能下降有交互协同作用。

Objective To analyze the elastic characteristics of ascending aorta in patients with high normal blood pressure and abdominal obesity by low-dose CT coronary angiography combined with CT fat quantification.Methods 173 employees over 40 years old were selected for physical examination in our hospital in 2015.All patients underwent 320 row low-dose CT coronary angiography and abdominal CT imaging.According to visceral adipose tissue and blood pressure,the subjects were divided into four groups,including high-normal blood pressure and abdominal obesity group(Group A,n=45),high-normal blood pressure and normal weight group(Group B,n=41),ideal blood pressure and abdominal obesity(Group C,n=36)and ideal blood pressure and normal weight(Normal group,n=51).The CT data of all participants were measured and calculated semi-automatically by Vitrea FX post-processing software,including the pressure strain elasticity coefficient(Ep)of ascending aorta,abdominal visceral adipose tissue(VAT)and abdominal subcutaneous adipose tissue(SAT).The scan volume CT dose index(CTDIvol),dose length product(DLP)of all patients were recorded.Results The Ep(287.15±26.73)of ascending aorta in Group A was significantly higher than that in Normal group(P<0.01),Group B and Group C(P<0.01).The Ep of ascending aorta in Group B(236.73±23.67)and Group C(242.61±23.29)were significantly higher than that in Normal group(P<0.01);There were no statistical differences between Group B and Group C in Ep(P>0.05).The results of multivariate covariance analysis showed that VAT(F=2.284,P=0.020)and systolic blood pressure(F=2.195,P=0.028)had significant effects in Ep and there was an interactive synergistic effect.Conclusion The elastic function of ascending aorta decreased with high-normal blood pressure and abdominal obesity.The increase of VAT and systolic blood pressure had an interactive synergistic effect on the decline of the elastic function of the ascending aorta.