应用超声二维应变成像技术评估肥厚型心肌病患者左心室心肌收缩的不同步性

Assessment of left ventricular dyssynchrony in patients with hypertrophic cardiomyopathy by two-dimensional strain echocardiography

目的应用超声二维应变成像技术评估肥厚型心肌病(HCM)患者左心室心肌收缩的不同步性。方法21例肥厚型心肌病患者、21例高血压病患者及21例正常人,分别记录并存储二尖瓣环、乳头肌及心尖部水平左心室短轴二维图像;获取其径向应变和圆周应变曲线。分别测量每个节段从心电图R波到峰值径向应变之间的时间(Trs)和从心电图R波到峰值圆周应变之间的时间(Tcs);并且分别计算每个患者18个节段Trs的标准差(Trs-18SD)和18个节段Tcs的标准差(Tcs-18SD)。将HCM组患者所有心肌节段分为肥厚节段与非肥厚节段心肌,比较两组间Trs和Tcs的差异。结果HCM组患者Trs-18SD明显高于HHD组患者及正常对照组[HCM组:(83±18)ms,HHD组:(52±15)ms,对照组:(46±9)ms,P<0.001],而高血压组与正常对照组之间无明显差异。HCM组患者Tcs-18SD明显高于HHD组患者及正常对照组[HCM组:(84±18)ms,HHD组:(48±10)ms,对照组:(46±10)ms,P<0.001],而高血压组与正常对照组之间无明显差异。肥厚节段心肌Trs明显低于非肥厚节段心肌(341±42vs388±40,P<0.05);而肥厚节段心肌Tcs虽然低于非肥厚节段心肌,但其差异无统计学意义。结论肥厚型心肌病患者左心室收缩存在不同步性,超声二维应变成像技术为评估左心室收缩不同步性提供了无创性新方法。

Objective To evaluate left ventricular （LV） dyssynchrony in patients with hypertrophic cardiomyopathy （HCM） by two-dimensional （2D） strain echocardiography. Methods Basal, middle, and apical 2D LV short-axis images were acquired in 21 patients with HCM, 21 patients with hypertension heart disease （HHD） and 21 age-matched controls. Time interval from the R-wave to peak radial strain （Trs）, and time to peak circumferential strain （Tcs） were measured in six equidistant segments at each level of the 3 LV short-axis views using 2D strain echocardiography. To assess LV dyssynchrony, Trs （cs）-18SD, the standard deviation （SD） of Trs （cs） in all 18 segments, was calculated. All segments of HCM were divided into hypertrophied and nonhypertrophied segments. Trs and Tcs of those were compared. Results Trs-18SD and Tes-18SD were significantly longer in patients with HCM than in age-matched controls and patients with HHD （[Trs- 18SD： HCM： [83±18]ms, HHD： [52±15]ms, control： [46±9]ms, P〈0.001; Tcs-18SD： HCM： [84±18]ms, HHD： [48±10]ms, control： [46±10]ms, P〈0. 001）. Trs was significantly shorter in hypertrophied segments than in nonhypertrophied segments in patients with DCM （341±42 vs 388±40, P〈0.05）. Conclusion Assessment of LV dyssynchrony by two-dimensional strain echocardiography was feasible in patients with HCM.