HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 288/4/H1546    most recent 00716.2004v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (11) Citing Articles via Google Scholar Google Scholar Articles by Cheng, A. Articles by Ingels, N. B. Search for Related Content PubMed PubMed Citation Articles by Cheng, A. Articles by Ingels, N. B., Jr.

Transmural cardiac strains in the lateral wall of the ovine left ventricle

¹Department of Cardiovascular and Thoracic Surgery, Stanford University School of Medicine, Stanford; ³Laboratory of Cardiovascular Physiology and Biophysics, Research Institute of the Palo Alto Medical Foundation, Palo Alto, California; and ²Department of Biomedical Engineering, Texas A&M University, College Station, Texas

Submitted 19 July 2004 ; accepted in final form 2 December 2004

The constant-volume property of contracting cardiac muscle has been invoked in models of heart wall mechanics that predict that systolic subendocardial left ventricular (LV) wall thickening must significantly exceed subepicardial thickening. To examine this prediction, we implanted arrays of radiopaque markers to measure lateral equatorial wall transmural strains and global and regional LV geometry in seven sheep and studied the four-dimensional dynamics of these arrays using biplane videofluoroscopy (60 Hz) in anesthetized intact animals 1 and 8 wk after surgery. A transmural gradient of systolic lateral wall thickening was observed at 1 wk (P = 0.009; linear regression) but was no longer present at 8 wk (P = 0.243). Referenced to end diastole, group mean (±SD) end-systolic radial subepicardial, midwall, and subendocardial wall thickening strains were, respectively, 0.08 ± 0.08, 0.14 ± 0.08, and 0.22 ± 0.12 at 1 wk and 0.19 ± 0.07 (P = 0.02; 1 vs. 8 wk), 0.20 ± 0.04, and 0.23 ± 0.07 at 8 wk. With the exception of an 8-ml (7%) increase in end-diastolic volume (P = 0.04) from 1 to 8 wk, LV shape and hemodynamics were otherwise unchanged. We conclude that equivalent hemodynamics can be generated by the left ventricle with or without a transmural gradient of systolic wall thickening in this region; thus such a gradient is unlikely to be a fundamental property of the contracting LV myocardium. We discuss some implications of these findings regarding mechanisms involved in systolic wall thickening.

wall thickening; left ventricle myocardium; systolic function

This article has been cited by other articles:

				C. J. Carlhall, T. C. Nguyen, A. Itoh, D. B. Ennis, W. Bothe, D. Liang, N. B. Ingels, and D. C. Miller Alterations in Transmural Myocardial Strain: An Early Marker of Left Ventricular Dysfunction in Mitral Regurgitation? Circulation, September 30, 2008; 118(14_suppl_1): S256 - S262. [Abstract] [Full Text] [PDF]

				A. Cheng, T. C. Nguyen, M. Malinowski, G. T. Daughters, D. C. Miller, and N. B. Ingels Jr Heterogeneity of Left Ventricular Wall Thickening Mechanisms Circulation, August 12, 2008; 118(7): 713 - 721. [Abstract] [Full Text] [PDF]

				H. Ashikaga, B. A. Coppola, K. G. Yamazaki, F. J. Villarreal, J. H. Omens, and J. W. Covell Changes in regional myocardial volume during the cardiac cycle: implications for transmural blood flow and cardiac structure Am J Physiol Heart Circ Physiol, August 1, 2008; 295(2): H610 - H618. [Abstract] [Full Text] [PDF]

				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]

				T. C. Nguyen, A. Cheng, F. A. Tibayan, D. Liang, G. T. Daughters, N. B. Ingels Jr., and D. C. Miller Septal-lateral annnular cinching perturbs basal left ventricular transmural strains Eur. J. Cardiothorac. Surg., March 1, 2007; 31(3): 423 - 429. [Abstract] [Full Text] [PDF]

				H. Ashikaga, B. A. Coppola, B. Hopenfeld, E. S. Leifer, E. R. McVeigh, and J. H. Omens Transmural Dispersion of Myofiber Mechanics: Implications for Electrical Heterogeneity In Vivo J. Am. Coll. Cardiol., February 27, 2007; 49(8): 909 - 916. [Abstract] [Full Text] [PDF]

				T. C. Nguyen, A. Cheng, F. Langer, F. Rodriguez, R. A. Oakes, A. Itoh, D. B. Ennis, D. Liang, G. T. Daughters, N. B. Ingels Jr, et al. Altered Myocardial Shear Strains Are Associated With Chronic Ischemic Mitral Regurgitation Ann. Thorac. Surg., January 1, 2007; 83(1): 47 - 54. [Abstract] [Full Text] [PDF]

				A. Cheng, T. C. Nguyen, M. Malinowski, F. Langer, D. Liang, G. T. Daughters, N. B. Ingels Jr, and D. C. Miller Passive Ventricular Constraint Prevents Transmural Shear Strain Progression in Left Ventricle Remodeling Circulation, July 4, 2006; 114(1_suppl): I-79 - I-86. [Abstract] [Full Text] [PDF]

				A. Cheng, T. C. Nguyen, M. Malinowski, D. Liang, G. T. Daughters, N. B. Ingels Jr, and D. C. Miller Effects of Undersized Mitral Annuloplasty on Regional Transmural Left Ventricular Wall Strains and Wall Thickening Mechanisms Circulation, July 4, 2006; 114(1_suppl): I-600 - I-609. [Abstract] [Full Text] [PDF]

				A. Cheng, F. Langer, F. Rodriguez, J. C. Criscione, G. T. Daughters, D. C. Miller, and N. B. Ingels Jr. Transmural sheet strains in the lateral wall of the ovine left ventricle Am J Physiol Heart Circ Physiol, September 1, 2005; 289(3): H1234 - H1241. [Abstract] [Full Text] [PDF]