Skip Navigation

Cardiovascular Research 2000 47(2):284-293; doi:10.1016/S0008-6363(00)00089-4
© 2000 by European Society of Cardiology
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow E-letters: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when E-letters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Mazhari, R.
Right arrow Articles by McCulloch, A. D
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Mazhari, R.
Right arrow Articles by McCulloch, A. D
Social Bookmarking
 Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Copyright © 2000, European Society of Cardiology

Structural basis of regional dysfunction in acutely ischemic myocardium

Reza Mazharia, Jeffrey H Omensa,b, James W Covella,b and Andrew D McCullocha,*

aDepartment of Bioengineering, The Whitaker Institute for Biomedical Engineering, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0412, USA
bDepartment of Medicine, The Whitaker Institute for Biomedical Engineering, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0412, USA

* Corresponding author. Tel.: +1-858-534-2547; fax: +1-858-534-6896 amcculloch{at}ucsd.edu

Objective: Impaired systolic function in the normally perfused myocardium adjacent to an ischemic region — the functional border zone — is thought to result from mechanical interactions across the perfusion boundary. We investigated how segment orientation and vessel involved affect regional strains in the functional border zone and whether altered stresses associated with a step transition in contractility can explain the functional border zone. Methods and results: Regional epicardial strain distributions were obtained from measured displacements of radiopaque markers in open-chest anesthetized canines, and related to local myofiber angles and blood flows. The functional border zone for fiber strain was significantly narrower than that for cross-fiber strain and significantly wider for left anterior descending (LAD) than left circumflex (LCx) coronary occlusion (1.23 vs. 0.45 cm). A detailed three-dimensional computational model with a one-to-one relation between perfusion and myofilament activation and no transitional zone of intermediate contractility showed close agreement with these observations and significantly elevated stresses in the border zone. Differences between LAD and LCx occlusions in the model were due to differences in left ventricular systolic pressure and not to differences in perfusion boundary or muscle fiber orientation. The border zone was narrower for fiber strain than cross-fiber strain because systolic stiffness is greatest along the muscle fiber direction. Conclusion: Abnormal regional mechanics in the acute ischemic border arise from increased wall stresses without a transitional zone of intermediate contractility. Perfusion is more tightly coupled to fiber than cross-fiber strain, and a wider functional border zone of fiber strain during LAD than LCx occlusion is primarily due to higher regional wall stresses rather than anatomic variations.

KEYWORDS Regional blood flow; Ventricular function; Contractile function; Hemodynamics


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
EuropaceHome page
P. Bordachar, L. Labrousse, J.-B. Thambo, P. Reant, S. Lafitte, M. D. O'Neill, P. Jais, M. Haissaguerre, J. Clementy, and P. Dos Santos
Haemodynamic impact of the left ventricular pacing site during graded ischaemia in an open-chest pig model
Europace, February 1, 2008; 10(2): 242 - 248.
[Abstract] [Full Text] [PDF]


Home page
Ann. Thorac. Surg.Home page
F. Langer, F. Rodriguez, A. Cheng, S. Ortiz, K. B. Harrington, M. K. Zasio, G. T. Daughters, J. C. Criscione, N. B. Ingels, and D. C. Miller
Alterations in Lateral Left Ventricular Wall Transmural Strains During Acute Circumflex and Anterior Descending Coronary Occlusion
Ann. Thorac. Surg., July 1, 2007; 84(1): 51 - 60.
[Abstract] [Full Text] [PDF]


Home page
Ann. Thorac. Surg.Home page
J. J. Pilla, A. S. Blom, J. H. Gorman III, D. J. Brockman, J. Affuso, L. M. Parish, H. Sakamoto, B. M. Jackson, M. A. Acker, and R. C. Gorman
Early Postinfarction Ventricular Restraint Improves Borderzone Wall Thickening Dynamics During Remodeling
Ann. Thorac. Surg., December 1, 2005; 80(6): 2257 - 2262.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
H. Ashikaga, S. R. Mickelsen, D. B. Ennis, I. Rodriguez, P. Kellman, H. Wen, and E. R. McVeigh
Electromechanical analysis of infarct border zone in chronic myocardial infarction
Am J Physiol Heart Circ Physiol, September 1, 2005; 289(3): H1099 - H1105.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
H. Ashikaga, J. H. Omens, and J. W. Covell
Time-dependent remodeling of transmural architecture underlying abnormal ventricular geometry in chronic volume overload heart failure
Am J Physiol Heart Circ Physiol, November 1, 2004; 287(5): H1994 - H2002.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
J. G. Barra, A. J. Crottogini, P. Willshaw, E. C. Lascano, and R. H. Pichel
Contribution of myocardium hydraulic skeleton to left ventricular wall interaction and synergy in dogs
Am J Physiol Heart Circ Physiol, August 1, 2004; 287(2): H896 - H904.
[Abstract] [Full Text] [PDF]


Home page
CirculationHome page
R. Mazhari, J. H. Omens, R. S. Pavelec, J. W. Covell, and A. D. McCulloch
Transmural Distribution of Three-Dimensional Systolic Strains in Stunned Myocardium
Circulation, July 17, 2001; 104(3): 336 - 341.
[Abstract] [Full Text] [PDF]



Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.