TY - JOUR
T1 - Influence of site of regional ischemia on LV cavity shape change in dogs
AU - Marino, P.
AU - Kass, D.
AU - Lima, J.
AU - Lowell Maughan, W.
AU - Graves, W.
AU - Weiss, J. L.
N1 - Copyright:
Copyright 2004 Elsevier B.V., All rights reserved.
PY - 1988
Y1 - 1988
N2 - We assessed whether altering the location of acute ischemia produced differing and consistent changes in cavity shape in the canine left ventricle. Twenty anesthetized open-chest dogs underwent transient occlusion of the left anterior descending (LAD) or circumflex (Circ) artery, and cavity shape change was recorded in two-dimensional short-axis echocardiograms. The extent of injury was assessed by radiolabeled microspheres. Shape was analyzed by converting digitized endocardial contours into polar form and expressing the result as a Fourier series. Series terms reflected specific shape deformations, ie., 2nd term would equal 'elongation', 3rd term would equal 'triangular'. During LAD occlusions, 32.5 ± 3.0% of the ventricle was hypoperfused compared with 29.8 ± 2.9% during Circ occlusions (NS). Normal ventricular shape became more circular during ejection indicated by a reduction in the power in nearly all of the Fourier spectra components. During Circ occlusion, the chamber became more elongated, seen in a 63 ± 16% rise in the 2nd component, and overall shape significantly less circular at end systole than at end diastole. LAD occlusion produced an entirely different pattern, one with no significant elongation but the development of a more triangular shape (86 ± 27% rise in the 3rd term) by end systole. We conclude that here are characteristic and contrasting shape deformations in LV short-axis contours that depend on the site of ischemic injury. These changes may relate to site-specific geometry and loading, and they point to potential limitations of left ventricular models that do not account for regional inhomogeneity.
AB - We assessed whether altering the location of acute ischemia produced differing and consistent changes in cavity shape in the canine left ventricle. Twenty anesthetized open-chest dogs underwent transient occlusion of the left anterior descending (LAD) or circumflex (Circ) artery, and cavity shape change was recorded in two-dimensional short-axis echocardiograms. The extent of injury was assessed by radiolabeled microspheres. Shape was analyzed by converting digitized endocardial contours into polar form and expressing the result as a Fourier series. Series terms reflected specific shape deformations, ie., 2nd term would equal 'elongation', 3rd term would equal 'triangular'. During LAD occlusions, 32.5 ± 3.0% of the ventricle was hypoperfused compared with 29.8 ± 2.9% during Circ occlusions (NS). Normal ventricular shape became more circular during ejection indicated by a reduction in the power in nearly all of the Fourier spectra components. During Circ occlusion, the chamber became more elongated, seen in a 63 ± 16% rise in the 2nd component, and overall shape significantly less circular at end systole than at end diastole. LAD occlusion produced an entirely different pattern, one with no significant elongation but the development of a more triangular shape (86 ± 27% rise in the 3rd term) by end systole. We conclude that here are characteristic and contrasting shape deformations in LV short-axis contours that depend on the site of ischemic injury. These changes may relate to site-specific geometry and loading, and they point to potential limitations of left ventricular models that do not account for regional inhomogeneity.
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M3 - Article
C2 - 3348433
AN - SCOPUS:0023909743
VL - 254
SP - 23/3
JO - American Journal of Physiology
JF - American Journal of Physiology
SN - 0363-6135
IS - 3
ER -