定量组织速度成像评价甲亢性心肌病兔不同左室构型右心功能的变化

目的:探讨定量组织速度成像(QTVI)技术评价甲状腺功能亢进(甲亢)性心肌病兔不同左室构型右心功能变化的价值。方法:新西兰纯种白兔30只,随机分为实验组(n=20只)和对照组(n=10只)。实验组腹腔注射左旋甲状腺素[45μg/(kg·d)×28 d]建立甲亢兔模型。实验组超声参数依据Ganau的分型方法分为两型:向心性肥厚亚组(CH亚组,n=7)和离心性肥厚亚组(EH亚组,n=11)。各组均行常规超声心动图及QTVI参数测定,包括三尖瓣前瓣环收缩期峰值速度(Vs)、收缩期加速度(a)和舒张期峰值速度(Ve)、舒张早期峰值血流速度(E)/Ve等。结果:CH亚组左室质量指数(LVMI)及相对室壁厚度(RWT)与对照组比较明显增加(均P0.01)。EH亚组LVMI与对照组比较明显增加(P0.01),而RWT与对照组比较差别无显著差异。CH亚组与对照组比较三尖瓣前瓣环Ve明显减低(P0.05),E/Ve明显增加(P0.05),但Vs、a与对照组比较差别无显著差异。EH亚组与对照组和CH亚组比较,三尖瓣前瓣环Ve、Vs和a明显减低(均P0.01),E/Ve明显增加(P0.05)。结论:QTVI技术可评价甲亢性心肌病兔不同左室构型右心室收缩及舒张功能的变化。

Evaluation of the change in right ventricular function in rabbits with hyperthyroid cardiomyopathy with different left ventricular geometry by quantitative tissue velocity imaging

AIM：To evaluate the change of right ventricular function in rabbits with hyperthyroid cardiomyopathy with different left ventricular geometry by quantitative tissue velocity imaging （QTVI）. METHODS： Thirty purebred New Zealand rabbits were randomly divided into experimental group （n=20） and control group （n=10）. Hyperthyroidism animal model was established by intraperitoneal injection of levothyroxine （L-Thy） [（45 μg/（kg·day）] for 28 days in the experimental group and according to the Ganau Classification, ultrasound parameters were divided into two groups： concentric hypertrophy （CH subgroup, n=7） and eccentric hypertrophy （EH subgroup, n=11）. Peak velocity during systole （Vs）, systolic acceleration （a）, peak velocity during diastole （Ve） and E/Ve at the anterior valve tricuspid annulus were measured by QTVI, and conventional echocardiographic parameters were also obtained. RESULTS： LVMI and RWT in CH group increased significantly （both P〈0.01）. LVMI in EH group increased obviously （P〈0.01）, but no significant difference in RWT was seen compared with that in control group. Ve in CH group was lower than that in control group （P〈0.05）. E/Ve in CH group was higher than that in control group （P〈0.05）, but no significant difference in Vs and a was found between CH group and control group （both P〉0.05）. Ve, Vs and a in EH group were significantly lower than those in CH group and control group （both P〈0.01）. E/Ve in EH groups was significantly higher than that in CH group and control group （P〈0.05）. CONCLUSIONS： QTVI can accurately assess the right ventricular systolic and diastolic functions in rabbits with hyperthyroid cardiomyopathy with different left ventricular geometry.