摘要
目的应用斑点追踪显像(speckle tracking imaging,STI)技术获取左束支传导阻滞(left bundle branch block,LBBB)动物模型的压力-应变环(pressure-strain loops,PSL),评估左心室心肌做功参数,以评价LBBB对左心室功能及运动模式的影响。方法选取24只健康雄性比格犬,麻醉状态下射频消融左束支制作LBBB模型,实时测量动脉压力。分别于造模前、造模成功后30 min(Acute-LBBB)、造模成功后3个月(Chronic-LBBB)获取心电图和超声心动图结果,应用STI技术测量左心室整体纵向应变(global longitudinal strain,GLS),并获取各时间点的PSL,评估左心室整体和节段心肌做功参数。结果与Baseline相比,Acute-LBBB、Chronic-LBBB左心室整体做功效率显著降低(P<0.05),整体无用功显著增加(P<0.01),Acute-LBBB的GLS显著降低(P=0.04)。造模前,室间隔基底段及中段做功效率、有用功均高于左室侧壁相应节段(P<0.01),而无用功节段值的分布则相反(P<0.01)。Acute-LBBB室间隔各节段心肌做功效率较造模前显著降低(基底段、中段、心尖段P<0.05)、无用功增加(P<0.05),室间隔基底段有用功降低(P=0.01),而侧壁基底段无用功增加(P=0.04)。Chronic-LBBB室间隔基底段与中段的心肌做功效率较Acute-LBBB轻度恢复(P=0.03),但仍显著低于造模前(P=0.001),其余各节段做功参数的改变与Acute-LBBB相似。结论急性及慢性LBBB均可导致左心室整体及节段做功能参数的改变。左心室心肌做功参数可以定量分析LBBB的左心室功能及运动模式的改变。
Objective To evaluate the left ventricular myocardial work parameters of the animal models with left bundle branch block(LBBB)and evaluate the effects of LBBB on left ventricular function and motion pattern by pressure-strain loops(PSL)of speckle tracking imaging(STI).Methods In Twenty-four healthy male beagles,LBBB was induced by radio frequency ablation under anesthesia,and blood pressure was measured at the same time.Electrocardiograms and echocardiography images were acquired before(baseline),30 minutes after(acute-LBBB)and 3 months after(chronic-LBBB)the creation of LBBB respectively.STI was applied to measure the left ventricular global longitudinal strain(GLS)and obtain the the PSL of each time point to evaluate the left ventricular global and segmental myocardial work parameters.Results Compared to the baseline,the global work efficiencies(GWE)were obviously reduced(P<0.05)and global wasted works(GWW)were significantly increased(P<0.01)in the acute-LBBB and chronic-LBBB,significant differences were observed in GLS between acute-LBBB and baseline(P=0.04).In baseline,the work efficiency(WEsept)and the constructive work(CWsept)in the basal and middle segments of the septal wall were both obviously higher than the corresponding segments of left ventricular lateral wall(P<0.01),while the distribution of the wasted work(WWsept)was opposite(P<0.01).In acute-LBBB,the WEsept of all segments were significantly decreased(P<0.05),the WWsept were obviously increased(P<0.05),the CWsept of basal segment was significantly reduced(P=0.01),while the wasted work in the basal segment of lateral wall(WWlat)was increased(P=0.04)compared with the baseline.Compared with the acute-LBBB,the WEsept of basal and middle segments were mildly recovery(P=0.03)in chronic-LBBB,but were still lower than the baseline(P=0.001),the changes of the other myocardial work parameters of septal and lateral wall were similar to the acute-LBBB.Conclusions Both acute-LBBB and chronic-LBBB can lead to the changes of left ventricular global and segmental myocardial work parameters.The myocardial work parameters of left ventricle can quantitatively analyze the changes of left ventricular function and motion pattern of the LBBB.
作者
葛贝贝
许迪
缪长青
李炎
李明霞
陈燕
张艳娟
龚婵娟
李鹏
王芳
沈艳
姚静
Ge Beibei;Xu Di;Miao Changqing;Li Yan;Li Mingxia;Chen Yan;Zhang Yanjuan;Gong Chanjuan;Li Peng;Wang Fang;Shen Yan;Yao Jing(Department of Cardiology,First Affiliated Hospital of Nanjing Medical University,Nanjing 210029,China)
出处
《中华超声影像学杂志》
CSCD
北大核心
2020年第9期799-806,共8页
Chinese Journal of Ultrasonography
基金
国家自然科学基金(81571691,81771844)。
关键词
超声心动描记术
左束支传导阻滞
心室功能
左
心肌做功
Echocardiography
Left bundle branch block
Ventricular function,left
Myocardial work
