心肌速度梯度技术对先天性甲状腺功能减低症患儿左心室心肌局部收缩功能的评价

Evaluation of regional myocardial systolic function of left ventricle in children with congenital hypothyroidism by myocardial velocity gradient technique

目的探讨心肌速度梯度(MVG)技术在评价先天性甲状腺功能低下症(CH)患儿左心室收缩功能方面的应用价值。方法应用定量组织速度成像(QTV I)技术分析35名CH患儿(CH组)及年龄匹配的30名正常婴幼儿(对照组)左心室心肌各节段长轴和短轴方向上的速度曲线,测量收缩期峰值运动速度(Vs),计算长轴和短轴方向上收缩期心肌速度梯度MVG1、MVG2和MVG3等参数。结果 CH患儿左心室后间隔、后壁、前间隔各节段MVG1、MVG2及MVG3较对照组减低明显,差异有统计学意义(P<0.05);CH患儿左室前壁基底段MVG3较对照组减低,差异有统计学意义(P<0.05);侧壁、下壁及前壁各节段MVG1、MVG2两组之间比较差异无统计学意义(P>0.05)。前壁中间段及心尖段、下壁及侧壁各节段MVG3两组之间比较差异无统计学意义(P>0.05)。结论 CH患儿左心室长轴和短轴方向心肌局部收缩功能在一定程度上存在降低,为临床早期干预提供依据。

Objective To explore the application value of myocardial velocity gradient （MVG） technique in evaluating systolic function of left ventricle of congenital hypothyroidism infants. Methods Quantitative tissue velocity imaging （QTVI） was used to analyze velocity curves in long axis and short axis of myocardium of left ventricle in 35 infants with congenital hypothyroidism （ CH group） and 30 healthy infants （control group） . Peak systolic velocity （Vs） was measured; systolic myocardial velocity gradient 1 （MVG1）, MVG2, and MVG3 in long axis and short axis were measured. Results MVG1, MVG2, and MVG3 in anterior septum, posterior septum, posterior wall of CH group were statistically significantly lower than those in control group （P〈0. 05） ; MVG3 in anterior basal segment of CH group was statistically significandy lower than that in control group （ P〈0.05 ） ; there was no statistically significant difference in MVG1 and MVG2 in side wall, inferior wall, and front wall between the two groups （P〉 0. 05） . There was no statistically significant difference in MVG3 in middle segment and apical segment of front wall, inferior wall, and side wall between the two groups （P〉 0. 05） . Conclusion The regional left ventricular systolic function in long axis and short axis of CH infants decrease, which provides a basis for early clinical intervention.