STI评价射血分数保留性心力衰竭患者左心室扭转运动变化的研究

Twist parameter of left ventricular assessed by speckle tracking imaging in heart failure patients with preserved ejection fraction

目的 :采用超声二维斑点追踪显像技术(Speckle tracking imaging,STI)评估射血分数保留性心力衰竭(Heart failure with preserved ejection fraction,HFpEF)患者左心室(Left ventricle,LV)扭转参数的变化,分析扭转参数是否对评估HFpEF患者LV心肌力学改变具有临床价值。方法:应用STI软件分析63例HFpEF患者扭转参数,包括心尖旋转角度峰值(Par)、心底旋转角度峰值(Pbr)及心尖与心底扭转角度纯差值——扭转角度峰值(Ptw)、扭转速度峰值(PtwV)、扭转达峰时间百分比(TPK%)、解旋速度峰值(PutwV)、等容舒张期解旋百分比(Iutw%);并与以下常规超声心动图参数对比:左室舒张末期内径(LVDD)、左室后壁厚度(LVPW)、室间隔厚度(IVS)、射血分数(EF)、左房容积指数(LAVI)、二尖瓣口舒张早期峰值流速(E)、二尖瓣口舒张早期峰值流速与舒张晚期峰值流速之比(E/A)、二尖瓣口舒张早期和血流峰值与组织多普勒二尖瓣环舒张早期峰值速度之比(E/e')。对照组为60例健康志愿者。结果:HFpEF患者LVDD和EF均在正常范围内(P>0.05),而LVPW、IVS、LAVI、E、E/A、E/e'均与对照组有明显统计学差异(P<0.01)。Par、PutwV、Iutw%均下降,与对照组相比差异有明显统计学意义(P<0.01)。Pbr、Ptw、PtwV、TPK%与正常组相比无明显差异(P>0.05)。PutwV、Iutw%均与E/A、E/e'呈明显正相关关系,与LAVI呈明显负相关关系。结论:STI评估左室舒张期解旋参数的改变能为临床诊断和治疗HFpEF提供心功能信息。收缩期心尖旋转角度峰值下降能敏感反映左室心肌功能受损,说明HFpEF患者也存在一些亚临床的收缩功能障碍。

Objective： To evaluate the twist parameters of left ventricular（LV） in heart failure patients with preserved ejection fraction（HFpEF） by speckle tracking imaging（STI）, and to analyze whether the twist parameters have clinical value in assessing the changes of LV myocardiac mechanics in HFpEF. Methods： 63 HFpEF patients were analyzed the following twist parameters by STI： peak apical rotation（Par）, Peak basal rotation（Pbr）, Peak LV twist（Ptw）, peak twist velocity（PtwV）, percent time to peak twist（TPK%）, peak untwisting velocity（Putw V） and isovolumic untwisting%（Iutw%）. The correlation between twist parameters and conventional echocardiography parameters were also analyzed. Conventional echocardiography parameters includes LV End-diastolic diameter（LVDD）, LV posterior wall（LVPW）, interventricular septum（IVS）, ejection fraction（EF）, left atrial volume index（LAVI）, peak of early diastolic mitral flow velocity（E）, ratio of peak early diastolic and peak late diastolic mitral flow velocity（E/A）, ratio of peak of early diastolic mitral flow velocity and early diastolic septal annular velocity（E/e＇）. 40 healthy volunteers were included as the control group. Results： LVDD and EF of HFpEF group were within the normal limits（P〉0.05）, but LVPW, IVS, LAVI, E, E/A, E/e＇ were all significantly different from the controls（P〈0.05）. The twist parameters show that systolic Par and diastolic Putw V and Iutw% were significantly lower in HFpEF group（P〈0.05）. Although Pbr, Ptw,PtwV, TPK% were decreased slightly, there is no significant difference compared with the controls（P〉0.05）. There were significant positive correlation between Putw V and E/A, E/e＇, as well as Iutw% and E/A, E/e＇. There was a significant negative correlation between LAVI and Putw V, Iutw%. Conclusions： The changes of diastolic untwist parameters measured by STI can provide information about LV myocardiac function in HFpEF patients to help clinical diagnosis and treatment. Reduced Par in HFpEF patients can sensitively reflect myocardiac dysfunction, denoting some degree of subclinical systolic dysfunction in these patients.