心房颤动状态下左心耳功能的超声应变率研究

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

目的应用应变率显像（SRI）分析持续性心房颤动（房颤）患者左心耳功能变化特点，探讨病理状态下左心耳机械运动的变化。方法分别选择29例持续性房颤患者和31例对照者，经食管超声心动图（TEE）获取左心耳超声图像，应用SRI技术对两组左心耳壁各节段应变率（SR）相关指标变化特点进行分析和比较。结果对照组中，左心耳壁顶部收缩期峰值应变率（SR）s和舒张期应变率（SRD）均高于其余节段（P〈O．01）。持续房颤组中，心耳顶部SRs仅高于间隔壁及侧壁中段（P〈0．05），心耳顶部SRD，仅高于间隔壁中段（P〈0．05）。持续房颤组各节段SRs和SRD较对照组均降低（P〈0．01）。对照组中，心耳顶部SRs与左心耳面积变化率和左心耳充盈速度呈正相关（r=0．724，0．637，P〈0．001）。结论左心耳顶部SRs决定了心耳整体的排空能力，房颤患者心耳壁的舒缩功能明显降低且失去有效协调运动。

Objective To assess the feasibility of left atrial appendage（LAA） function with strain rate imaging in patients with persistent atrial fibrillation（AF）,and to detect its movement characteristics under pathological conditions. Methods Thirty-one controls and twenty-nine suffers with persistent AF were included. Strain rate（SR） of systolie（SRs） and diastolie（SRD） of LAA wall were measured respectively in 5 segments and offline analyzed with dedicated software. LAA emptying velocities （LAA-EV） and filling velocities（LAA FV） were obtained by transesophageal echocardiography. Results SRs and SRD were higher at the tip of LAA than other segments in control group （ P〈0.01 ）;the SRs at the tip was higher than the middle part on the lateral and septal wall（ P 〈0.05） ,while the SRD at the tip was higher than the middle part of the septal wall in AF group （ P〈0.05）. SRs and SRD at all segments were higher in control group than their corresponding parts in AF group （ P〈0.01 ）. In control group, SRs taken from the tip were positively correlated with LAA-EV and LAA ejection fraction （LAA-EF）（ r = 0. 724,0. 637, P〈0. 001 ,respectively）. Conclusions The tip SRs plays an important role in LAA emptying. The systolic and diastolic functions of LAA are significant impaired in AF patients and LAA movements in AF patients are out of coordination.