组织速度成像结合应变率成像技术对房颤状态下左心耳功能的评价

Assessment of the left atrial appendage function by strain rate imaging and tissue velocity imaging in patients with atrial fibrillation

目的应用应变率成像(SRI)结合组织速度(TVI)显像技术评价持续性房颤患者左心耳机械运动特点以及变化特点。方法对29例患者和31例对照者行经食管超声检查,比较各节段运动速度(PSV和PDVE)以及局部心肌沿长轴的应变率(Ssr和Dsr)变化特点。结果对照组左心耳壁顶部Ssr、Dsr、PSV和PDVE均高于其余节段(P<0.01,0.05)。房颤组左心耳顶部Ssr、PSV仅高于间隔壁及侧壁中段(P<0.05),心耳顶部Dsr仅高于间隔壁中段(P<0.05)。对照组心耳顶部Ssr、PSV与左心耳面积变化率(LAA-EF)和左心耳充盈速度(LAA-EV)呈正相关(r=0.724、0.637、0.656、0.712,P<0.001),房颤组心耳顶部PSV与LADd呈线性负相关(r=-0.66,P<0.001)。房颤组各节段Ssr、Dsr、PSV以及PDVE较对照组均降低(P<0.01)。结论左心耳顶部Ssr以及PSV决定了心耳整体的排空能力,房颤患者由于心耳壁舒缩功能明显降低导致的心耳壁运动不协调。TVI和SRI技术相结合,能更为全面地反映左心耳功能变化特点。

Objective To assess left atrial appendage （LAA） function by using strain rate imaging （SRI） and tissue velocity imaging （TVI） in patients with persistent atrial fibrillation （AF）. Methods Thirty-one controls and 29 persistent AF patients are studied. The parameters of SRI and TVI are performed with offline analysis in 5 segments of LAA wall. Results At the tip of LAA, Ssr, Dsr, PSV and PDVE are higher than other segments in control group （P〈0.01）. In AF group, the tip Ssr and PSV are higher than the middle part of the lateral and the septal wall （P〈0.05）, while the tip Dsr is higher than the middle part of the septal wall （P〈0.05）. Ssr and PSV taken from the tip of the LAA are positively correlated with LAA-EV and LAA-EF （r=0.724, 0.637, 0.656, 0.712,P〈0.001, respectively）. In control group, Ssr taken from the tip of the LAA were positively correlated with LAA-EV and LAA-EF （r=0.724, 0.637, P〈0.001, respectively）. In AF group, Ssr taken from the tip of the LAA were negatively correlated with left atrium dimension （r=-0.528, P〈0.01）. PSV taken from the tip of the LAA are negatively correlated with LADd （r=-0.66, P〈0.001）. At the tip of LAA, PSV and PDVE are higher in control group than AF group （P〈0.01）. Conclusion SRI combined with TVI have high evaluative values in assessing LAA function. The tip Ssr and PSV play an important role in evaluating LAA systolic function. The movements of LAA in AF patients are out of coordination.