速度向量成像技术检测胎儿右心室长轴节段功能的临床研究

目的 应用速度向量成像(VVI)技术检测胎儿右心室长轴节段功能.方法 分别检测170例正常胎儿右室游离壁和室间隔右室壁各节段长轴心肌速度、应变和应变率,并观察其与孕周的关系.结果 胎儿右室壁收缩期和舒张期峰值速度由基底段向心尖段递减(P＜0.05),峰值应变和应变率无明显变化(P＞0.05);右室壁收缩期和舒张期峰值速度随孕周增加而增加(P＜0.05),峰值应变和应变率与孕周无明显关系(P＞0.05).结论 胎儿右室壁收缩期和舒张期峰值速度随妊娠进展增加,峰值应变和应变率保持不变,表明胎儿右室功能在妊娠中期已基本发育成熟.

Assessment of regional right ventricular longitudinal function in fetus using velocity vector imaging

Objective To evaluate regional right ventricular longitudinal function in fetus using velocity vector imaging(VVI),and establish nomogram of right ventricle,Methods One hundreed and seventy healthy fetuses were divided into 5 groups according to the gestational age.Dynamic digital views of four chamber view were collected and analyzed offline.Velocity,strain and strain rate were calculated in systolic and diastolic period,respectively.Results Normal systolic and diastolic values for velocity,strain and strain rate were established.Tissue velocity gradually decreased from the base segment to the apical segment(P＜0.05),whereas strain and strain rate were stable(P＞0.05).Tissue velocity was gestationalage dependent(P＜0.05),whereas strain and strain rate were stable throughout gestation (P＞0.05).Conclusions Fetal myocardial velocity,strain and strain rate measurements are easy to obtain and reproducible.Increase in tissue velocity throughout gestation probably reflects the growth of the fetal heart,whereas intrinsic myocardial properties as measured by strain and strain rate do not change.