Faculty Collaboration Database

Changes in passive but not active mechanical properties predict recovery of function of stunned myocardium. Ann Biomed Eng 1999;27(2):131-40

Date

04/13/1999

Pubmed ID

10199689

DOI

10.1114/1.167

Scopus ID

2-s2.0-0033090423 (requires institutional sign-in at Scopus site)   8 Citations

Abstract

The time course of alterations in active and passive mechanical properties of stunned myocardium during ischemia and throughout reperfusion has not been thoroughly quantified. This investigation tested the hypothesis that the amount of injury as well as the rate and extent of recovery of contractile function in postischemic, reperfused myocardium are directly correlated to changes in regional active and passive elastance and viscosity. A modified viscoelastic Voigt model was employed to quantify myocardial mechanical properties. Left ventricular pressure and segment length (in both ischemic and normal regions) were fit to the model consisting of an active elastic spring in parallel with a viscous damper and a passive elastic spring. The mechanical properties of myocardium from dogs which recovered (> or = 50%) baseline regional contractile function as determined by percent segment shortening (n=7) were compared to those from dogs that did not recover function (n=7). Both groups displayed decreased active elastance in the ischemic region during coronary artery occlusion, and this decrease was maintained in the nonrecovery group. Increases in viscosity of ischemic myocardium were observed in both groups during coronary occlusion but returned to control only in the recovery group. The nonrecovery group demonstrated increased passive elastance in the ischemic region during coronary occlusion and throughout the reperfusion period whereas the recovery group remained unchanged. We conclude that functional recovery of stunned myocardium is directly related to alterations in mechanical properties caused by ischemia and that changes in passive elastance during occlusion may predict the ability of ischemic myocardium to recover contractile function.

Author List

Schmeling TJ, Hettrick DA, Kersten JR, Pagel PS, Warltier DC

MESH terms used to index this publication - Major topics in bold

Animals
Computer Simulation
Coronary Circulation
Dogs
Elasticity
Female
Hemodynamics
Linear Models
Male
Models, Cardiovascular
Myocardial Contraction
Myocardial Stunning
Predictive Value of Tests
Reference Values
Regional Blood Flow
Signal Processing, Computer-Assisted
Ventricular Function, Left
Viscosity