Joseph Susan, Moazami Nader, Cupps Brian P, Howells Analyn, Craddock Heidi, Ewald Greg, Rogers Joseph, Pasque Michael K
Division of Cardiology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
J Heart Lung Transplant. 2009 Apr;28(4):388-94. doi: 10.1016/j.healun.2008.12.018. Epub 2009 Feb 13.
Myocardial systolic strain patterns in dilated cardiomyopathy are considered non-homogeneous but have not been investigated with magnetic resonance imaging (MRI)-based multiparametric systolic strain analysis. Left ventricular (LV) 3-dimensional (3D) multiparametric systolic strain analysis is sensitive to regional contractility and is generated from sequential MRI of tissue-tagging gridline-point displacements.
Sixty normal human volunteers underwent MRI-based 3D systolic strain analysis to supply normal average and standard deviation values for each of three strain parameters at each of 15,300 individual LV grid-points. Patient-specific multiparametric systolic strain data from each dilated cardiomyopathy patient (n = 10) were then subjected to a point-by-point comparison (n = 15,300 LV points) to the normal strain database for three individual strain components (45,900 database comparisons per patient). The resulting composite multiparametric Z-score values (standard deviation from normal average) were color contour mapped over patient-specific 3D LV geometry to detect the normalized regional contractile patterns associated with dilated cardiomyopathy.
Average multiparametric strain Z-score values varied significantly according to ventricular level (p = 0.001) and region (p = 0.003). Apical Z-scores were significantly less than those in both the base (p = 0.037) and mid-ventricle (p = 0.002), whereas anterolateral wall Z-scores were less than those in the anteroseptal (p = 0.023) and posteroseptal walls (p = 0.028).
MRI-based multiparametric systolic strain analysis suggests that myocardial systolic strain in patients with dilated cardiomyopathy has a heterogeneous regional distribution and, on average, falls almost 2 standard deviations from normal.
扩张型心肌病的心肌收缩期应变模式被认为是非均匀的，但尚未通过基于磁共振成像（MRI）的多参数收缩期应变分析进行研究。左心室（LV）三维（3D）多参数收缩期应变分析对局部收缩性敏感，由组织标记网格线点位移的连续MRI生成。
60名正常人类志愿者接受了基于MRI的3D收缩期应变分析，以提供15300个LV网格点中每个点的三个应变参数的正常平均值和标准差。然后，将每位扩张型心肌病患者（n = 10）的特定患者多参数收缩期应变数据与正常应变数据库进行逐点比较（n = 15300个LV点），针对三个单独的应变分量（每位患者进行45900次数据库比较）。将得到的复合多参数Z评分值（相对于正常平均值的标准差）在特定患者的3D LV几何结构上进行彩色轮廓映射，以检测与扩张型心肌病相关的标准化局部收缩模式。
平均多参数应变Z评分值根据心室水平（p = 0.001）和区域（p = 0.003）有显著差异。心尖部的Z评分显著低于心底（p = 0.037）和心室中部（p = 0.002），而前侧壁的Z评分低于前间隔壁（p = 0.023）和后间隔壁（p = 0.028）。
基于MRI的多参数收缩期应变分析表明，扩张型心肌病患者的心肌收缩期应变具有异质性区域分布，平均比正常水平低近2个标准差。
