三维斑点追踪技术评价早期肥厚型心肌病患者左心室局部收缩功能

摘要

目的 应用三维斑点追踪成像(3D-STI)技术评价早期肥厚型心肌病(HCM)患者左心室局部收缩功能.方法 连续纳入早期HCM患者70例,同期纳入健康志愿者70例作为对照组.实时三维超声获取左心室三维全容积图像,运用TomTec脱机分析软件对左室16个节段的纵向应变、圆周应变、径向应变以及整体应变等三维参数进行分析,比较两组间上述各参数的差异.结果 与对照组比较,早期HCM患者左心室收缩末期及舒张末期容积显著减小,每搏量显著减少,左室质量指数显著增加,舒张末期室间隔厚度显著增加,舒张末期后壁厚度增加(均P＜0.001),左室射血分数差异无统计学意义(P＞0.05);与对照组相比,HCM患者增厚节段纵向应变明显减低(P＜0.05),而径向、圆周应变明显增加(P＜0.05),整体应变差异无统计学意义(P＞0.05),其他非增厚节段的纵向、径向、圆周及整体应变差异多无统计学意义.室间隔厚度与室间隔纵向应变之间存在线性正相关性(r=0.287,P=0.006).结论 早期HCM患者存在局部心肌收缩功能损害,主要表现为增厚部位纵向应变减低,且与室壁肥厚的程度相关;而圆周及径向应变增加.3D-STI可用于早期HCM患者左心室局部收缩功能的评价.%Objective To assess the left ventricular (LV) regional systolic function by threedimensional speckle tracking imaging (3D-STI) in patients with early stage of hypertrophic cardiomyopathy (HCM).Methods A total of 70 consecutive patients with early stage of HCM were enrolled.In addition,70 healthy subjects were recruited as a control group.A real-time dynamic 3D echocardiography system (IE33) was used to acquire and store LV full-volume 3D images.LV 16 segments longitudinal strain,radial strain,circumferential strain and global strain were analyzed using off-line TomTec software.The difference between the two groups was compared.Results Compared with the control group,LV end diastolic,endsystolic volumes and stroke volume significantly decreased,while LV mass and LV interventricular septum diastolic thickness significantly increased,LV posterior wall diastolic thickness slightly increased (P ＜ 0.001).However,LVEF had no significant difference (P ＞0.05).Compared with the control group,the results were as followed:the longitudinal strain significantly reduced in hypertrophic segments(P ＜0.05),while circumferential and radial strain significantly increased (P ＜ 0.05),global strain showed no significantly difference (P ＞ 0.05).While longitudinal,radial and circumferential strain had no statistical differences in non-hypertrophic segments.A positive linear correlation existed between LV interventricular thickness and LV interventricular longitudinal strain (r =0.287,P =0.006).Conclnsions The impairment of regional myocardial contractility existed in early stage of HCM.The main features were longitudinal strain decreased in hypertrophic segments,which associated with the degree of LV wall thickness,while circumferential and radial strain increased.3D-STI provided a new method for evaluating LV regional systolic function in patients with early stage of HCM.