Browse by author
Lookup NU author(s): Professor Bob Anderson
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
© The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. Recent morphological studies provide evidence that the ventricular walls are arranged as a 3D meshwork of aggregated cardiomyocyte chains, exhibiting marked local structural variations. In contrary to previous findings, up to two-fifths of the chains are found to have a partially transmural alignment, thus deviating from the prevailing tangential orientation. Upon contraction, they produce, in addition to a tangential force, a radial force component that counteracts ventricular constriction and aids widening of the ventricular cavity. In experimental studies, we have provided evidence for the existence of such forces, which are auxotonic in nature. This is in contrast to the tangentially aligned myocytes that produce constrictive forces, which are unloading in nature. The ventricular myocardium is, therefore, able to function in an antagonistic fashion, with the prevailing constrictive forces acting simultaneously with a dilatory force component. The ratio of constrictive to dilating force varies locally according to the specific mural architecture. Such antagonism acts according to local demands to preserve the ventricular shape, store the elastic energy that drives the fast late systolic dilation and apportion mural motion to facilitate the spiralling nature of intracavitary flow. Intracavitary pressure and flow dynamics are thus governed concurrently by ventricular constrictive and dilative force components. Antagonistic activity, however, increases deleteriously in states of cardiac disease, such as hypertrophy and fibrosis. β-blockade at low dosage acts selectively to temper the auxotonic forces.
Author(s): Lunkenheimer PP, Niederer P, Stephenson RS, Redmann K, Batista RV, Smerup M, Anderson RH
Publication type: Review
Publication status: Published
Journal: European Journal of Cardio-Thoracic Surgery
Print publication date: 01/04/2018
Online publication date: 09/11/2017
Acceptance date: 01/10/2017
ISSN (print): 1010-7940
ISSN (electronic): 1873-734X
Publisher: European Association for Cardio-Thoracic Surgery