Remodeling after acute myocardial infarction: mapping ventricular dilatation using three dimensional CMR image registration
Author(s)
Type
Journal Article
Abstract
Background: Progressive heart failure due to remodeling is a major cause of morbidity and mortality following
myocardial infarction. Conventional clinical imaging measures global volume changes, and currently there is no
means of assessing regional myocardial dilatation in relation to ischemic burden. Here we use 3D co-registration of
Cardiovascular Magnetic Resonance (CMR) images to assess the long-term effects of ischemia-reperfusion injury on
left ventricular structure after acute ST-elevation myocardial infarction (STEMI).
Methods: Forty six patients (age range 33–77 years) underwent CMR imaging within 7 days following primary
percutaneous coronary intervention (PPCI) for acute STEMI with follow-up at one year. Functional cine imaging and
Late Gadolinium Enhancement (LGE) were segmented and co-registered. Local left ventricular wall dilatation was
assessed by using intensity-based similarities to track the structural changes in the heart between baseline and
follow-up. Results are expressed as means, standard errors and 95% confidence interval (CI) of the difference.
Results: Local left ventricular remodeling within infarcted myocardium was greater than in non-infarcted
myocardium (1.6% ± 1.0 vs 0.3% ± 0.9, 95% CI: -2.4% – -0.2%, P = 0.02). One-way ANOVA revealed that transmural
infarct thickness had a significant effect on the degree of local remodeling at one year (P < 0.0001) with greatest
wall dilatation observed when infarct transmurality exceeded 50%. Infarct remodeling was more severe when
microvascular obstruction (MVO) was present (3.8% ± 1.3 vs −1.6% ± 1.4, 95% CI: -9.1% – -1.5%, P = 0.007) and when
end-diastolic volume had increased by >20% (4.8% ± 1.4 vs −0.15% ± 1.2, 95% CI: -8.9% – -0.9%, P = 0.017).
Conclusions: The severity of ischemic injury has a significant effect on local ventricular wall remodeling with only
modest dilatation observed within non-ischemic myocardium. Limitation of chronic remodeling may therefore
depend on therapies directed at modulating ischemia-reperfusion injury. CMR co-registration has potential for
assessing dynamic changes in ventricular structure in relation to therapeutic interventions.
myocardial infarction. Conventional clinical imaging measures global volume changes, and currently there is no
means of assessing regional myocardial dilatation in relation to ischemic burden. Here we use 3D co-registration of
Cardiovascular Magnetic Resonance (CMR) images to assess the long-term effects of ischemia-reperfusion injury on
left ventricular structure after acute ST-elevation myocardial infarction (STEMI).
Methods: Forty six patients (age range 33–77 years) underwent CMR imaging within 7 days following primary
percutaneous coronary intervention (PPCI) for acute STEMI with follow-up at one year. Functional cine imaging and
Late Gadolinium Enhancement (LGE) were segmented and co-registered. Local left ventricular wall dilatation was
assessed by using intensity-based similarities to track the structural changes in the heart between baseline and
follow-up. Results are expressed as means, standard errors and 95% confidence interval (CI) of the difference.
Results: Local left ventricular remodeling within infarcted myocardium was greater than in non-infarcted
myocardium (1.6% ± 1.0 vs 0.3% ± 0.9, 95% CI: -2.4% – -0.2%, P = 0.02). One-way ANOVA revealed that transmural
infarct thickness had a significant effect on the degree of local remodeling at one year (P < 0.0001) with greatest
wall dilatation observed when infarct transmurality exceeded 50%. Infarct remodeling was more severe when
microvascular obstruction (MVO) was present (3.8% ± 1.3 vs −1.6% ± 1.4, 95% CI: -9.1% – -1.5%, P = 0.007) and when
end-diastolic volume had increased by >20% (4.8% ± 1.4 vs −0.15% ± 1.2, 95% CI: -8.9% – -0.9%, P = 0.017).
Conclusions: The severity of ischemic injury has a significant effect on local ventricular wall remodeling with only
modest dilatation observed within non-ischemic myocardium. Limitation of chronic remodeling may therefore
depend on therapies directed at modulating ischemia-reperfusion injury. CMR co-registration has potential for
assessing dynamic changes in ventricular structure in relation to therapeutic interventions.
Date Issued
2012-06-21
Date Acceptance
2012-06-21
Citation
Journal of Cardiovascular Magnetic Resonance, 2012, 14
ISSN
1532-429X
Publisher
BioMed Central
Journal / Book Title
Journal of Cardiovascular Magnetic Resonance
Volume
14
Copyright Statement
© 2012 O'Regan et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited.
Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited.
License URL
Subjects
Science & Technology
Life Sciences & Biomedicine
Cardiac & Cardiovascular Systems
Radiology, Nuclear Medicine & Medical Imaging
Cardiovascular System & Cardiology
CARDIAC & CARDIOVASCULAR SYSTEMS
RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING
Cardiovascular magnetic resonance
Acute myocardial infarction
Image analysis
PRIMARY CORONARY ANGIOPLASTY
NO-REFLOW PHENOMENON
MAGNETIC-RESONANCE
MR-IMAGES
MICROVASCULAR OBSTRUCTION
CLINICAL IMPLICATIONS
PROBABILISTIC ATLAS
32-CHANNEL COIL
CARDIAC MR
HEART
Publication Status
Published
Article Number
ARTN 41