Time-dependent remodeling of transmural architecture underlying abnormal ventricular geometry in chronic volume overload heart failure

Hiroshi Ashikaga, Jeffrey H. Omens, James W. Covell

Research output: Contribution to journalArticlepeer-review

Abstract

To test the hypothesis that the abnormal ventricular geometry in failing hearts may be accounted for by regionally selective remodeling of myocardial laminae or sheets, we investigated remodeling of the transmural architecture in chronic volume overload induced by an aortocaval shunt. We determined three-dimensional finite deformation at apical and basal sites in left ventricular anterior wall of six dogs with the use of biplane cineradiography of implanted markers. Myocardial strains at end diastole were measured at a failing state referred to control to describe remodeling of myofibers and sheet structures over time. After 9 ± 2 wk (means ± SE) of volume overload, the myocardial volume within the marker sets increased by >20%. At 2 wk, the basal site had myofiber elongation (0.099 ± 0.030; P < 0.05), whereas the apical site did not [P = not significant (NS)]. Sheet shear at the basal site increased progressively toward the final study (0.040 ± 0.003 at 2 wk and 0.054 ± 0.021 at final; both P < 0.05), which contributed to a significant increase in wall thickness at the final study (0.181 ± 0.047; P < 0.05), whereas the apical site did not (P = NS). We conclude that the remodeling of the transmural architecture is regionally heterogeneous in chronic volume overload. The early differences in fiber elongation seem most likely due to a regional gradient in diastolic wall stress, whereas the late differences in wall thickness are most likely related to regional differences in the laminar architecture of the wall. These results suggest that the temporal progression of ventricular remodeling may be anatomically designed at the level of regional laminar architecture.

Original languageEnglish (US)
Pages (from-to)H1994-H2002
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Volume287
Issue number5 56-5
DOIs
StatePublished - Nov 2004

Keywords

  • Fiber
  • Finite deformation
  • Heart failure
  • Myocardial lamina

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)

Fingerprint Dive into the research topics of 'Time-dependent remodeling of transmural architecture underlying abnormal ventricular geometry in chronic volume overload heart failure'. Together they form a unique fingerprint.

Cite this