title: Exploring cardiac biophysical properties.
abstract: The heart is subject to multiple sources of stress. To maintain its normal function, and successfully overcome these stresses, heart muscle is equipped with fine-tuned regulatory mechanisms. Some of these mechanisms are inherent within the myocardium itself and are known as intrinsic mechanisms. Over a century ago, Otto Frank and Ernest Starling described an intrinsic mechanism by which the heart, even ex vivo, regulates its function on a beat-to-beat basis. According to this phenomenon, the higher the ventricular filling is, the bigger the stroke volume. Thus, the Frank-Starling law establishes a direct relationship between the diastolic and systolic function of the heart. To observe this biophysical phenomenon and to investigate it, technologic development has been a pre-requisite to scientific knowledge. It allowed for example to observe, at the cellular level, a Frank-Starling like mechanism and has been termed: Length Dependent Activation (LDA). In this review, we summarize some experimental systems that have been developed and are currently still in use to investigate cardiac biophysical properties from the whole heart down to the single myofibril. As a scientific support, investigation of the Frank-Starling mechanism will be used as a case study.
authors.affiliation: Qatar Cardiovascular Research Center, Qatar Foundation, Doha, Qatar.
authors.forename: Younss
authors.initials: Y
authors.lastname: Ait Mou
authors.affiliation: Qatar Cardiovascular Research Center, Qatar Foundation, Doha, Qatar.
authors.forename: Christian
authors.initials: C
authors.lastname: Bollensdorff
authors.affiliation: U1046 INSERM - UMR9214 CNRS- Université de Montpellier, Montpellier, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Cazorla
authors.affiliation: Qatar Cardiovascular Research Center, Qatar Foundation, Doha, Qatar.
authors.forename: Yacoub
authors.initials: Y
authors.lastname: Magdi
authors.affiliation: Department of Cell and Molecular Physiology, Heath Science Division, Loyola University Chicago, Maywood, Illinois 60153.
authors.forename: Pieter P
authors.initials: PP
authors.lastname: de Tombe