跳动和停跳猪心脏中斑片状和大面积心肌梗死的三维MRI评估：与显微镜检查的对比验证

Three-dimensional MRI assessments of patchy and large myocardial infarction in beating and nonbeating swine hearts: validation with microscopy.

作者信息

Jablonowski Robert, Wilson Mark W, Joudi Noor, Hetts Steven W, Saeed Maythem

机构信息

Department of Radiology and Biomedical Imaging, School of Medicine, University of California San Francisco, 185 Berry St, Suite 350, Campus Box 0946, San Francisco, CA 94107-5705.

出版信息

Acad Radiol. 2014 Aug;21(8):1048-55. doi: 10.1016/j.acra.2014.03.012.

DOI:10.1016/j.acra.2014.03.012

PMID:25018077

Abstract

RATIONALE AND OBJECTIVES

To measure and validate patchy and large myocardial infarction (MI) at 3 days and 5 weeks in beating and nonbeating hearts using contrast-enhanced three-dimensional (3D) inversion-recovery gradient echo (IR-GRE) magnetic resonance imaging (MRI) and microscopy.

MATERIALS AND METHODS

Pigs (n = 28) were subjected to 1) patchy MI (group I), 2) large MI (group II), or 3) combined (patchy and large) MI (groups III and IV) using microemboli and/or 90-minute left anterior descending (LAD) occlusion and imaged at 3 days and 5 weeks after interventions. Gadolinium diethylenetriamine penta-acetic acid (Gd-DTPA)-enhanced 3D and two-dimensional (2D) IR-GRE were performed for comparison in beating and nonbeating hearts. Macroscopic histochemical and microscopic histopathologic measurements were used for validation.

RESULTS

Three-dimensional images demonstrated hyperenhanced patchy microinfarction, large MI, hypoenhanced/hyperenhanced microvascular obstruction, and infarct resorption. Acute and chronic combined MI on 3D was underestimated compared to microscopy (bias: -1.8 ± 3.8%) but overestimated acute large infarction. In beating and nonbeating hearts, close correlations/agreements were found between 3D/2D acquisitions in all groups (beating hearts: r = 0.70-0.99; bias: group I 0.47 ± 2.0%, II 0.33 ± 1.2%, III 0.54 ± 1.5%, and IV 0.28 ± 1.0%).

CONCLUSIONS

The 3D IR-GRE underestimated the extent of acute and chronic combined MI compared to microscopic measurements. This sequence may have the potential to differentiate patchy from large MI and demonstrate MI healing after coronary interventions.

摘要

原理与目的

使用对比增强三维（3D）反转恢复梯度回波（IR - GRE）磁共振成像（MRI）和显微镜技术，在第3天和第5周时测量并验证跳动和停跳心脏中的散在性和大面积心肌梗死（MI）。

材料与方法

28头猪分别接受以下处理：1）散在性心肌梗死（I组），2）大面积心肌梗死（II组），或3）联合（散在性和大面积）心肌梗死（III组和IV组），采用微栓塞和/或90分钟左前降支（LAD）闭塞，并在干预后第3天和第5周进行成像。在跳动和停跳心脏中进行钆喷酸葡胺（Gd - DTPA）增强的3D和二维（2D）IR - GRE检查以作比较。采用宏观组织化学和微观组织病理学测量进行验证。

结果

三维图像显示了高增强的散在性微梗死、大面积心肌梗死、低增强/高增强微血管阻塞以及梗死吸收情况。与显微镜检查相比，3D上的急性和慢性联合心肌梗死被低估（偏差：-1.8±3.8%），但急性大面积梗死被高估。在跳动和停跳心脏中，所有组的3D/2D采集之间均发现密切的相关性/一致性（跳动心脏：r = 0.70 - 0.99；偏差：I组0.47±2.0%，II组0.33±1.2%，III组0.54±1.5%，IV组0.28±1.0%）。