斑点追踪显像评价束支传导阻滞患者左心室短轴方向的收缩同步性

目的 探讨完全性左束支传导阻滞(CLBBB)及完全性右束支传导阻滞(CRBBB)患者左心室短轴方向的收缩同步情况.方法 选取28例CLBBB患者包括左心室收缩功能正常(CLBBBa组,15例)及左心室收缩功能不全(CLBBBb组,13例)者]、29例CRBBB患者包括左心室收缩功能正常(CRBBBa组,16例)及左心室收缩功能不全(CRBBBb组,13例)者]及对照组25例无心血管疾病者,应用斑点追踪显像技术分析左心室二尖瓣水平、乳头肌水平及心尖水平径向应变、周向应变以及旋转角度收缩期达峰时间,计算收缩期达峰时间标准差.结果 除CLBBBa组心尖水平周向应变收缩期达峰时间外,CLBBB患者径向应变、旋转角度及周向应变收缩期达峰时间较对照组明显增加(P均＜0.05),CRBBBb组径向应变收缩期达峰时间较对照组明显增加(P均＜0.05).CLBBB患者径向应变、周向应变及旋转角度收缩期达峰时间标准差较对照组明显增加(P均＜0.05).CRBBBb组径向应变收缩期达峰时间标准差大于CRBBBa组和对照组(P＜0.05).结论 CLBBB患者存在明显心肌收缩不同步现象,左心室收缩功能不全CRBBB患者心肌存在径向应变上收缩不同步现象.

Assessment of left ventricular systolic synchrony in patients with bundle branch block using speckle tracking imaging

Objective To assess left ventricular systolic synchrony in short-axis direction in patients with complete left bundle-branch block (CLBBB) and complete right bundle-branch block (CRBBB). Methods Twenty-eight CLBBB patients (including 15 with normal left ventricular systolic function CLBBBa group] and 13 with left ventricular systolic dysfunction CLBBBb group]), 29 CRBBB patients (including 16 with normal left ventricular systolic function CRBBBa group] and 13 with left ventricular systolic dysfunction CRBBBb group]), as well as 25 controls without cardiovascular diseases were enrolled and analyzed with speckle tracking imaging. Time to peak systolic radial strain, circumferential strain and time to peak systolic rotation angle at mitral valve level, papillary muscle level, apex cordis level were measured, respectively, and the the standard deviation of these parameters were calculated. Results Compared with control group, time to peak systolic strain of radial, circumferential strain and time to peak systolic rotation angle (except time to peak systolic circumferential strain at apex cordis level in CLBBBa group) increased in CLBBB patients (all P<0.05), and time to peak systolic radial strain increased in CRBBBb group (all P<0.05). Compared with CRBBBa and control group, the standard deviation of time to peak systolic radial strain, systolic circumferential strain and systolic rotation angle increased in CLBBB patients (all P<0.05), and the standard deviation of time to peak systolic radial strain increased in CRBBBb group (P<0.05). Conclusion There is significant systolic dyssynchrony in CLBBB patients, as well as in radial strain of CRBBB patients with left ventricular systolic dysfunction.