超声心动图定量组织速度成像评价动脉粥样硬化兔心肌功能

Evaluation of myocardial functional change in rabbit model with coronary artery atherosclerosis by quantitative tissue velocity imaging

目的:探讨超声心动图定量组织速度成像评价动脉粥样硬化(AS)兔模型整体及局部心肌功能的应用价值。方法:20只兔分为2组:10只为AS组,以高脂饮食饲养12周建立AS模型;10只为正常组,以普通饲料饲养。成模后行常规超声心动图检测左室短轴缩短率(FS)、射血分数(EF)、二尖瓣口血流速度(E)等指标;定量组织速度成像(QTVI)检测后间隔、前侧壁、前壁和下壁中段局部心肌收缩期峰值速度(Sm)和舒张期峰值速度(Em);检测并计算二尖瓣环后间隔、前侧壁、前壁和下壁4个位点收缩期峰值速度的平均值(Sa)作为QTVI整体收缩功能指标,舒张期峰值速度的平均值(Ea)和二尖瓣口舒张期血流速度E与Ea的比值(E/Ea)作为QTVI整体舒张功能指标。结果:①常规超声心动图指标EF[(66.6±4.5):(68.2±5.7)%]、FS[(33.6±3.2):(34.9±4.3)%]及二尖瓣口血流速度E[(0.9±0.1):(0.9±0.1)m/s]在2组间差异无显著性。②QTVI指标显示AS组整体心功能降低,表现为Sa[(4.3±1.0):(6.1±0.6)cm/s]和Ea[(3.8±1.4):(6.8±0.7)cm/s]降低,E/Ea升高(0.17±0.08:0.09±0.02)。③QTVI指标显示AS组局部心肌功能下降,表现为前壁[(2.3±1.7):(4.9±2.1)cm/s]和下壁[(3.7±1.6):(5.5±1.1)cm/s]中段心肌Em降低,下壁中段心肌Sm降低[(3.0±0.6):(4.3±0.5)cm/s]。结论:QTVI是评价AS兔模型整体及局部心肌功能的敏感方法。

Objective：To evaluate the value of quantitative tissue velocity imaging（QTVI） in assessing myocardial functional change in rabbit model with coronary artery artherosclerosis. Methods： The 20 rahbits were divided into two groups. The atheroslerosis group （AS group） included 10 rabbits fed with superfatted food for 12 weeks to model atherosclerosis. The normal group included another 10 rabbits fed with normal food for the same period. Routine eehocardiography was performed in all rabbits to detect fraction shortening （FS）, ejection fraction （EF） and the peak dialstolic blood velociy in mitral valve orifice （E）. Quantitative tissue velocity imaging （QTVI） was performed in all rabbits. Peak systolic velocity and peak diastolic velocity derived from quantitative tissue velocity curve at mitral valve annulus （Sa, Ea） and middle segments of posterior interventricular septum, left ventricular anter01ateral, anterior and inferior wall （Sm, Era） were mesured. Sa and Ea were averaged for the whole myocardial function, and the ratio of E and Ea （E/Ea） was calculated. Results：（1）EF （[66.6±4.5]% vs [8. 2±5. 7]%）, FS （[33.6±3.2%] vs [34.9±4.3]%） and E （[0.9±0.1] vs [0.9±0.1]m/s） were not significantly different between two groups. （2）In QTVI, the whole myocardial function decreased in AS group with Sa （[4.3± 1.0] vs [6.1±0.6] cm/s） and Ea （[3.8 ± 1.4] vs [6.8±0.7] cm/s） decreased and E/Ea（[0.17 ± 0.08] vs [0.09 ± 0. 02]）increased, （3）In QTVI, the regional myocardial function decreased in AS group with Em decreased in middle segments of left ventrieular anterior wall （[2.3 ± 1.7] vs [4.9 ± 2.1] cm/s） and inferior wall （[3.7±1.6] vs [5.5±1. 1]cm/s）and Sm decreased in the middle segment of inferior wall （[3.0±0.6] vs [4. 3±0.5]cm/s）. Conclusions.. QTVI is sensitive in assessing myocardial functional change in rabbit model with coronary artery artherosclerosis.