斑点追踪成像评价心脏淀粉样变性患者左心室心肌分层应变

Left Ventricular Myocardial Strain in Patients with Cardiac Amyloidosis Using Speckle Tracking Imaging

目的探讨采用斑点追踪成像(STI)评价心脏淀粉样变性(CA)患者左心室内膜下心肌和外膜下心肌收缩功能的价值。资料与方法 20例CA患者(CA组)和30例健康志愿者(对照组)分别行二维超声心动图检查,测量左心室各短轴平面内膜下、外膜下及整体心肌收缩期圆周应变(CS)峰值和径向应变(RS)峰值,计算左心室整体内膜下、外膜下心肌收缩期CS峰值和RS峰值。结果与对照组比较,CA组舒张末期室间隔厚度及左心室后壁厚度、收缩末期左心房内径、二尖瓣口舒张期血流峰速/舒张末期血流峰速、二尖瓣口舒张早期血流峰速/二尖瓣环舒张早期运动速度均明显增高(P<0.01)。左心室射血分数、舒张末期血流峰速、E波速度下降时间、二尖瓣环收缩期运动速度、舒张早期运动速度、舒张晚期运动速度明显减低(P<0.01);舒张末期左心室内径、二尖瓣口舒张早期血流峰速无显著差异(P>0.05)。CA组和对照组左心室短轴二尖瓣水平、乳头肌水平、心尖水平及左心室整体内膜下心肌收缩期CS峰值高于外膜下心肌(P<0.001)。对照组内膜下心肌收缩期RS峰值高于外膜下心肌(P<0.001),CA组内膜下心肌收缩期RS值均低于外膜下心肌(P<0.05)。与对照组比较,CA组左心室二尖瓣水平、乳头肌水平、心尖水平内膜下、外膜下及平面整体心肌收缩期CS峰值和RS峰值均减低(P<0.001),左心室整体内膜下、外膜下心肌收缩期CS峰值和RS峰值均减低(P<0.001),且内膜下心肌减低更明显。结论 STI可以评价CA患者左心室圆周及径向心肌收缩功能,可作为临床早期诊断CA和评价病变程度的无创性检查方法。

Purpose To evaluate the systolic function of left ventricular subendocardial and subepicardial myocardium using speckle tracking imaging （STI） in patients with cardiac amyloidosis. Materials and Methods Twenty patients with cardiac amyloidosis （CA group ） and thirty healthy subjects （control group） were examined using two- dimensional echocardiography. High frame rate two-dimensional images were recorded at left ventricular short-axis views during three consecutive cardiac cycles on basal, papillary muscle and apical planes. Peak systolic circumferential strain （CS） and radial strain （RS） were measured in subendocardial, subepicardial and transmural myocardium. The mean CS and RS were calculated in subendocardial and subepicardial myocardium. Results Compared with control group, IVSd, LVPWDd, LAESd, E/A and E/e of CA group were significantly increased （P〈0.01）. LVEF, A, DT, s, e and a of CA group were significantly decreased （P〈0.01）. No significant difference was found in LVEDd and E between the two groups （P〉0.05）. In three short-axis and global views, CS of subendocardial myocardium was higher than that of subepicardial myocardium in both CA group and control group （P〈0.001）. RS of subendocardial myocardium was higher than that of subepicardiaI myocardium in control group （P〈0.001）. However, the RS of subendocardial myocardium was lower than that of subepicardial myocardium in CA group （P〈0.05）. Furthermore, the CS and RS of subendocardial, subepicardial and transmural myocardium in three shortaxis views （basal, papillary muscle and apical planes） in the CA group were significantly decreased （P〈0.001）. The mean CS and RS of endocardial and epicardial myocardium in the CA group were significantly decreased （P〈0.001）. Conclusion CS and RS of transmural ventricular wall can be traced with STI and will be useful for early evaluation of the CA severity.