Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.

OBJECTIVES: To evaluate possible mechanism for delayed hyperenhancement of scarred myocardium by investigating the relationship of contrast agent (CA) first pass and delayed enhancement patterns with histopathological changes. MATERIALS AND METHODS: Eighteen pigs underwent 4 weeks ligation of 1 or 2...

Full description

Bibliographic Details
Main Authors: Jian Wang, Bo Xiang, Hung-Yu Lin, Hongyu Liu, Darren Freed, Rakesh C Arora, Ganghong Tian
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2014-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC4011786?pdf=render
_version_ 1818275759422177280
author Jian Wang
Bo Xiang
Hung-Yu Lin
Hongyu Liu
Darren Freed
Rakesh C Arora
Ganghong Tian
author_facet Jian Wang
Bo Xiang
Hung-Yu Lin
Hongyu Liu
Darren Freed
Rakesh C Arora
Ganghong Tian
author_sort Jian Wang
collection DOAJ
description OBJECTIVES: To evaluate possible mechanism for delayed hyperenhancement of scarred myocardium by investigating the relationship of contrast agent (CA) first pass and delayed enhancement patterns with histopathological changes. MATERIALS AND METHODS: Eighteen pigs underwent 4 weeks ligation of 1 or 2 diagonal coronary arteries to induce chronic infarction. The hearts were then removed and perfused in a Langendorff apparatus. The hearts firstly experienced phosphorus 31 MR spectroscopy. The hearts in group I (n = 9) and II (n = 9) then received the bolus injection of Gadolinium diethylenetriamine pentaacetic acid (0.05 mmol/kg) and gadolinium-based macromolecular agent (P792, 15 µmol/kg), respectively. First pass T2* MRI was acquired using a gradient echo sequence. Delayed enhanced T1 MRI was acquired with an inversion recovery sequence. Masson's trichrome and anti- von Willebrand Factor (vWF) staining were performed for infarct characterization. RESULTS: Wash-in of both kinds of CA caused the sharp and dramatic T2* signal decrease of scarred myocardium similar to that of normal myocardium. Myocardial blood flow and microvessel density were significantly recovered in 4-week-old scar tissue. Steady state distribution volume (ΔR1 relaxation rate) of Gd-DTPA was markedly higher in scarred myocardium than in normal myocardium, whereas ΔR1 relaxation rate of P792 did not differ significantly between scarred and normal myocardium. The ratio of extracellular volume to the total water volume was significantly greater in scarred myocardium than in normal myocardium. Scarred myocardium contained massive residual capillaries and dilated vessels. Histological stains indicated the extensively discrete matrix deposition and lack of cellular structure in scarred myocardium. CONCLUSIONS: Collateral circulation formation and residual vessel effectively delivered CA into scarred myocardium. However, residual vessel without abnormal hyperpermeability allowed Gd-DTPA rather than P792 to penetrate into extravascular compartment. Discrete collagen fiber meshwork and loss of cellularity enlarged extracellular space accessible to Gd-DTPA, resulting in the delayed hyper-enhanced scar.
first_indexed 2024-12-12T22:34:51Z
format Article
id doaj.art-2c60d5ffb018452d8d4e0f8da451c61a
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-12T22:34:51Z
publishDate 2014-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-2c60d5ffb018452d8d4e0f8da451c61a2022-12-22T00:09:29ZengPublic Library of Science (PLoS)PLoS ONE1932-62032014-01-0195e9646310.1371/journal.pone.0096463Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.Jian WangBo XiangHung-Yu LinHongyu LiuDarren FreedRakesh C AroraGanghong TianOBJECTIVES: To evaluate possible mechanism for delayed hyperenhancement of scarred myocardium by investigating the relationship of contrast agent (CA) first pass and delayed enhancement patterns with histopathological changes. MATERIALS AND METHODS: Eighteen pigs underwent 4 weeks ligation of 1 or 2 diagonal coronary arteries to induce chronic infarction. The hearts were then removed and perfused in a Langendorff apparatus. The hearts firstly experienced phosphorus 31 MR spectroscopy. The hearts in group I (n = 9) and II (n = 9) then received the bolus injection of Gadolinium diethylenetriamine pentaacetic acid (0.05 mmol/kg) and gadolinium-based macromolecular agent (P792, 15 µmol/kg), respectively. First pass T2* MRI was acquired using a gradient echo sequence. Delayed enhanced T1 MRI was acquired with an inversion recovery sequence. Masson's trichrome and anti- von Willebrand Factor (vWF) staining were performed for infarct characterization. RESULTS: Wash-in of both kinds of CA caused the sharp and dramatic T2* signal decrease of scarred myocardium similar to that of normal myocardium. Myocardial blood flow and microvessel density were significantly recovered in 4-week-old scar tissue. Steady state distribution volume (ΔR1 relaxation rate) of Gd-DTPA was markedly higher in scarred myocardium than in normal myocardium, whereas ΔR1 relaxation rate of P792 did not differ significantly between scarred and normal myocardium. The ratio of extracellular volume to the total water volume was significantly greater in scarred myocardium than in normal myocardium. Scarred myocardium contained massive residual capillaries and dilated vessels. Histological stains indicated the extensively discrete matrix deposition and lack of cellular structure in scarred myocardium. CONCLUSIONS: Collateral circulation formation and residual vessel effectively delivered CA into scarred myocardium. However, residual vessel without abnormal hyperpermeability allowed Gd-DTPA rather than P792 to penetrate into extravascular compartment. Discrete collagen fiber meshwork and loss of cellularity enlarged extracellular space accessible to Gd-DTPA, resulting in the delayed hyper-enhanced scar.http://europepmc.org/articles/PMC4011786?pdf=render
spellingShingle Jian Wang
Bo Xiang
Hung-Yu Lin
Hongyu Liu
Darren Freed
Rakesh C Arora
Ganghong Tian
Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.
PLoS ONE
title Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.
title_full Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.
title_fullStr Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.
title_full_unstemmed Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.
title_short Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.
title_sort pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging
url http://europepmc.org/articles/PMC4011786?pdf=render
work_keys_str_mv AT jianwang pathologicalmechanismfordelayedhyperenhancementofchronicscarredmyocardiumincontrastagentenhancedmagneticresonanceimaging
AT boxiang pathologicalmechanismfordelayedhyperenhancementofchronicscarredmyocardiumincontrastagentenhancedmagneticresonanceimaging
AT hungyulin pathologicalmechanismfordelayedhyperenhancementofchronicscarredmyocardiumincontrastagentenhancedmagneticresonanceimaging
AT hongyuliu pathologicalmechanismfordelayedhyperenhancementofchronicscarredmyocardiumincontrastagentenhancedmagneticresonanceimaging
AT darrenfreed pathologicalmechanismfordelayedhyperenhancementofchronicscarredmyocardiumincontrastagentenhancedmagneticresonanceimaging
AT rakeshcarora pathologicalmechanismfordelayedhyperenhancementofchronicscarredmyocardiumincontrastagentenhancedmagneticresonanceimaging
AT ganghongtian pathologicalmechanismfordelayedhyperenhancementofchronicscarredmyocardiumincontrastagentenhancedmagneticresonanceimaging