Biomechanics of Cardiac Function

Abstract

The heart pumps blood to maintain circulation and ensure the delivery of oxygenated blood to all the organs of the body. Mechanics play a critical role in governing and regulating heart function under both normal and pathological conditions. Biological processes and mechanical stress are coupled together in regulating myocyte function and extracellular matrix structure thus controlling heart function. Here we offer a brief introduction to the biomechanics of left ventricular function and then summarize recent progress in the study of the effects of mechanical stress on ventricular wall remodeling and cardiac function as well as the effects of wall mechanical properties on cardiac function in normal and dysfunctional hearts. Various mechanical models to determine wall stress and cardiac function in normal and diseased hearts with both systolic and diastolic dysfunction are discussed. The results of these studies have enhanced our understanding of the biomechanical mechanism in the development and remodeling of normal and dysfunctional hearts. Biomechanics provide a tool to understand the mechanism of left ventricular remodeling in diastolic and systolic dysfunction and guidance in designing and developing new treatments.

Dynamic Loading of Human Engineered Heart Tissue Enhances Contractile Function and Drives Desmosome-linked Disease Phenotype

“…6). This finding is in line with previous in vivo results suggesting that tissue remodeling, including chamber thinning and eccentric dilation, is accelerated with elevated ventricular wall stresses (51,52). In fact, elevated ventricular wall stresses have been proposed to drive the infarct expansion seen post-myocardial infarction (53,54), as well as increase ventricular dilation in dilated cardiomyopathy patients (55)(56)(57).…”

Pseudoaneurysm Development after Free Wall Rupture Post Myocardial Infarction

“…The structural complications can be explained by understanding the first two of four steps in wound healing after AMI [ 3 ]. The first step is the acute ischemic phase and occurs within 4–6 h after the ischemic where a transient increase in the compliance of the left ventricular (LV) wall is noted with a decrease in the contractility of the ischemic region [ 3 ]. This results in a progressive thinning of the scarred tissue and eventual stiffness of the infarcted region [ 3 ].…”

“…The first step is the acute ischemic phase and occurs within 4–6 h after the ischemic where a transient increase in the compliance of the left ventricular (LV) wall is noted with a decrease in the contractility of the ischemic region [ 3 ]. This results in a progressive thinning of the scarred tissue and eventual stiffness of the infarcted region [ 3 ]. The second phase is the necrotic phase and lasts for 5–7 days after the event and is characterized by unchanged end-diastolic lengths of ischemic regions, indicative of even stiffer LV walls [ 3 ].…”

Mechanical Regulation of Protein Translation in the Cardiovascular System

“…The activity and integrity of the heart itself is highly influenced by biomechanics and mechanical stress is a critical mediator of cardiomyocyte function and extracellular matrix composition (Voorhees and Han, 2015). Biomechanical forces regulate the activity and function of the cells of the heart: cardiomyocytes, fibroblasts, and the vascular cells of the coronary blood vessels (Hahn and Schwartz, 2009;Voorhees and Han, 2015;van Putten et al, 2016;Herum et al, 2017). In response to biomechanical stress, cardiomyocytes undergo hypertrophic growth (Hannan et al, 2003).…”