超声应变显像技术评价肥厚性心肌病局部心肌功能的探讨

目的探讨超声组织应变显像(SI)技术评估肥厚性心肌病(HCM)患者局部心肌收缩与舒张功能的价值.方法 HCM患者30例,25例正常人为对照组.选取标准的心尖四腔切面,在心动周期中分别测量室间隔与左室侧壁基底段、中间段、心尖段沿心脏长轴方向上的收缩期峰值应变(εet),观察HCM组出现的收缩期反向应变节段;统计两组室间隔中段和后壁中段的收缩后应变(PSS)节段数并计算其幅度值;将室间隔中段的应变值与室壁厚度进行相关分析.结果①正常组各节段εet从心底至心尖呈逐渐减低趋势,但节段间差异无显著性意义(P＞0.05);②HCM组与正常组εet比较,HCM组各节段应变均显著降低(P＜0.05);③HCM组内室间隔中段应变最低,与基底段、心尖段比较差异有显著性意义(P＜0.05),本组病例大约40%的肥厚节段收缩期可见反向应变;④病变组和正常组均存在PSS,然而与病变组比较正常组PSS节段少、幅度低(P＜0.05);⑤HCM组和正常组室间隔中段的εet与室壁厚度密切相关(r＝0.83).结论 HCM患者无论肥厚节段或非肥厚节段均存在收缩舒张功能减低,且以肥厚节段病损更重,应变显像技术能对其进行准确评价.

Assessment of regional myocardial function in patients with hypertrophic cardiomyopathy by tissue strain imaging

Objective To assess regional myocardial systolic and diastolic function in patients with hypertrophic cardiomyopathy(HCM) by tissue strain imaging(SI).Methods Doppler echocardiography and SI were performed in patients with HCM(n=30) and age-matched healthy subjects(n=25) at apical four-chamber view.Regional longitudinal peak systolic strain was measured at basal,mid and apical segments of septal and lateral walls in both groups,compared between both groups and between intragroup,reversed segments were observed in HCM group.Meantime,post-systolic strain(PSS) segment numbers were counted and its amplitude was calculated;Correlation was analyzed between peak systolic strain and thickness in mid-septum.Results Peak systolic strain of different segment in patients with HCM was significant reduced than those in control group(P<0.05),peak systolic strain in the mid-septum was lowest and reversed segments were found in 40% thickening segment in the HCM group;PSS presents in both HCM and control groups,but amplitude of PSS in control group was less(P<0.05);There was a significant correlation between peak systolic strain and thickness in mid-septum(r=0.83).Conclusion Left ventricular regional myocardial systolic and diastolic function has been impaired in patients with HCM,especially in thickening segments.SI is a sensitive and accurate technology to detect it.