TY - JOUR
T1 - Evaluation of regional load in acute ischemia by three-dimensional curvatures analysis of the left ventricle
AU - Lessick, J.
AU - Sideman, S.
AU - Azhari, H.
AU - Shapiro, E.
AU - Weiss, J. L.
AU - Beyar, R.
PY - 1993/3
Y1 - 1993/3
N2 - Geometric remodeling of the left ventricle (LV) following myocardial infarction and ischemic insult is associated with myocardial load redistribution. Regional curvatures based on 3-D reconstructions of the LV are used to calculate the regional loads. The technique uses surface normals to derive local circumferential and meridional curvatures. Following the validation of the procedure on simple geometric shapes, the effect of acute ischemia on the regional load redistribution was studied in six open chest dogs. Short axis magnetic resonance imaging (MRI) scans were used to reconstruct end-diastolic (ED) and end-systolic (ES) LV images by applying our helical shape descriptor, before and after acute coronary occlusion. Regional curvatures as well as local wall thickness by the volume element method were calculated before and after acute ischemia, and were used to approximate regional loads, by a regional stress index (σ/P). Postmortem evaluation using monastral blue staining was used to divide each LV to normal (NZ), ischemic (IZ), and border (BZ) zones in the ischemic case, and to the anatomically matched regions in the preischemic LVs. Ischemia affects the local curvatures and loads both at ED and ES. at ED, σ/P rose significantly only in the IZ. Similarly, at ES, the highest increase in load was detected in the IZ, but increases in circumferential and meridional load were seen in all regions. Identifying the load redistribution following acute ischemia helps delineate the mechanisms affecting geometric LV remodeling following myocardial infarction.
AB - Geometric remodeling of the left ventricle (LV) following myocardial infarction and ischemic insult is associated with myocardial load redistribution. Regional curvatures based on 3-D reconstructions of the LV are used to calculate the regional loads. The technique uses surface normals to derive local circumferential and meridional curvatures. Following the validation of the procedure on simple geometric shapes, the effect of acute ischemia on the regional load redistribution was studied in six open chest dogs. Short axis magnetic resonance imaging (MRI) scans were used to reconstruct end-diastolic (ED) and end-systolic (ES) LV images by applying our helical shape descriptor, before and after acute coronary occlusion. Regional curvatures as well as local wall thickness by the volume element method were calculated before and after acute ischemia, and were used to approximate regional loads, by a regional stress index (σ/P). Postmortem evaluation using monastral blue staining was used to divide each LV to normal (NZ), ischemic (IZ), and border (BZ) zones in the ischemic case, and to the anatomically matched regions in the preischemic LVs. Ischemia affects the local curvatures and loads both at ED and ES. at ED, σ/P rose significantly only in the IZ. Similarly, at ES, the highest increase in load was detected in the IZ, but increases in circumferential and meridional load were seen in all regions. Identifying the load redistribution following acute ischemia helps delineate the mechanisms affecting geometric LV remodeling following myocardial infarction.
KW - Curvature
KW - Left ventricle
KW - Regional function
KW - Three-dimensional
KW - Ventricular remodeling
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U2 - 10.1007/BF02367610
DO - 10.1007/BF02367610
M3 - Article
C2 - 8484563
AN - SCOPUS:0027557190
SN - 0090-6964
VL - 21
SP - 147
EP - 161
JO - Annals of biomedical engineering
JF - Annals of biomedical engineering
IS - 2
ER -