title: Evaluation of the Differences of Myocardial Fibers between Acute and Chronic Myocardial Infarction: Application of Diffusion Tensor Magnetic Resonance Imaging in a Rhesus Monkey Model.
abstract: To understand microstructural changes after myocardial infarction (MI), we evaluated myocardial fibers of rhesus monkeys during acute or chronic MI, and identified the differences of myocardial fibers between acute and chronic MI.
  
  
  
  Six fixed hearts of rhesus monkeys with left anterior descending coronary artery ligation for 1 hour or 84 days were scanned by diffusion tensor magnetic resonance imaging (MRI) to measure apparent diffusion coefficient (ADC), fractional anisotropy (FA) and helix angle (HA).
  
  
  
  Comparing with acute MI monkeys (FA: 0.59 ± 0.02; ADC: 5.0 ± 0.6 × 10(-4) mm(2)/s; HA: 94.5 ± 4.4°), chronic MI monkeys showed remarkably decreased FA value (0.26 ± 0.03), increased ADC value (7.8 ± 0.8 × 10(-4)mm(2)/s), decreased HA transmural range (49.5 ± 4.6°) and serious defects on endocardium in infarcted regions. The HA in infarcted regions shifted to more components of negative left-handed helix in chronic MI monkeys (-38.3 ± 5.0°-11.2 ± 4.3°) than in acute MI monkeys (-41.4 ± 5.1°-53.1 ± 3.7°), but the HA in remote regions shifted to more components of positive right-handed helix in chronic MI monkeys (-43.8 ± 2.7°-66.5 ± 4.9°) than in acute MI monkeys (-59.5 ± 3.4°-64.9 ± 4.3°).
  
  
  
  Diffusion tensor MRI method helps to quantify differences of mechanical microstructure and water diffusion of myocardial fibers between acute and chronic MI monkey's models.
authors: Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041, China.; CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology of China, Beijing 100190, China.
authors: Yuqing
authors: Y
authors: Wang
authors: Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041, China.; Department of Radiology, Beijing Jishuitan Hospital, 4th Clinical Medical College of Peking University, Beijing 100035, China.
authors: Wei
authors: W
authors: Cai
authors: Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041, China.
authors: Lei
authors: L
authors: Wang
authors: Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041, China.; Department of Radiology, The First Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China.
authors: Rui
authors: R
authors: Xia
authors: Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041, China.; Department of Radiology, The First Affiliated Hospital of Kunming Medical University, Yunnan 650032, China.
authors: Wei
authors: W
authors: Chen
authors: Mallinckrodt Institute of Radiology, School of Medicine, Washington University, St. Louis, MO 63110, USA.
authors: Jie
authors: J
authors: Zheng
authors: Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041, China.
authors: Fabao
authors: F
authors: Gao
mesh_terms: D000208:Acute Disease; D000818:Animals; D016880:Anisotropy; D002908:Chronic Disease; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D056324:Diffusion Tensor Imaging / Q000379:methods; D004195:Disease Models, Animal; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D008253:Macaca mulatta; D008297:Male; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000473:pathology*; D032383:Myocytes, Cardiac / Q000473:pathology*
keywords: DTI; Diffusion tensor MR imaging; Helix angle; Myocardial fiber; Myocardial infarction; Rhesus monkey