Neizel Mirja, Lossnitzer Dirk, Korosoglou Grigorios, Schäufele Tim, Peykarjou Hooman, Steen Henning, Ocklenburg Christina, Giannitsis Evangelos, Katus Hugo A, Osman Nael F
Medical Clinic III, University Hospital Heidelberg, Heidelberg, Germany.
Circ Cardiovasc Imaging. 2009 Mar;2(2):116-22. doi: 10.1161/CIRCIMAGING.108.789032. Epub 2009 Jan 26.
Strain-encoded imaging (SENC) is a new technique for myocardial deformation analysis in cardiac MRI. The aim of the study was, therefore, to evaluate whether myocardial deformation imaging performed by SENC allows for quantification of regional left ventricular function and is related to transmurality states of infarcted tissue in patients with acute myocardial infarction.
Cardiac MRI was performed in 38 patients with acute myocardial infarction 3+/-1 days after successful reperfusion using a clinical 1.5-T MRI scanner. Ten healthy volunteers served as controls. SENC is a technique that directly measures peak circumferential strain from long-axis views and peak longitudinal strain from short-axis views. Measurements were obtained for each segment in a modified 17-segment model. Wall motion and infarcted tissue were evaluated semiquantitatively from steady-state free-precession cine sequences and contrast-enhanced MR images and were then related to myocardial strain. Comparison of peak circumferential strain assessed by SENC and MR tagging was performed. In total, 456 segments were analyzed. Peak circumferential and longitudinal strain calculated from SENC images was significantly different in regions defined as normokinetic, hypokinetic, or akinetic (P<0.001). A cutoff peak systolic circumferential strain value of -10% differentiated nontransmural from transmural infarcted myocardium, with a sensitivity of 97% and a specificity of 94%. Strain analysis of SENC and MR tagging correlated well (r=0.76) with narrow limits of agreement (-9.9% to 8.5%).
SENC provides rapid and objective quantification of regional myocardial function and allows discrimination between different transmurality states in patients with acute myocardial infarction.
应变编码成像（SENC）是心脏磁共振成像（MRI）中用于心肌变形分析的一项新技术。因此，本研究的目的是评估通过SENC进行的心肌变形成像是否能够对局部左心室功能进行定量分析，以及是否与急性心肌梗死患者梗死组织的透壁状态相关。
使用临床1.5-T MRI扫描仪，对38例急性心肌梗死患者在成功再灌注3±1天后进行心脏MRI检查。10名健康志愿者作为对照。SENC是一种直接从长轴视图测量峰值圆周应变和从短轴视图测量峰值纵向应变的技术。在改良的17节段模型中对每个节段进行测量。从稳态自由进动电影序列和对比增强MR图像中对室壁运动和梗死组织进行半定量评估，然后将其与心肌应变相关联。对通过SENC和MR标记评估的峰值圆周应变进行比较。总共分析了456个节段。在定义为运动正常、运动减弱或无运动的区域，从SENC图像计算出的峰值圆周应变和纵向应变有显著差异（P<0.001）。收缩期峰值圆周应变值-10%可区分非透壁性梗死心肌和透壁性梗死心肌，敏感性为97%，特异性为94%。SENC和MR标记的应变分析相关性良好（r=0.76），一致性界限较窄（-9.9%至8.5%）。
SENC可快速、客观地对局部心肌功能进行定量分析，并能够区分急性心肌梗死患者不同的透壁状态。
