Influence of left-ventricular shape on passive filling properties and end-diastolic fiber stress and strain

Choi, Hon Fai; D'hooge, Jan; Rademakers, Frank; Claus, Piet

doi:10.1016/j.jbiomech.2010.02.022

Cited by 36 publications

(38 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The diastolic geometry created with ANSYS DesignModeler [ Fig. 2(a)] consisted of a truncated prolate spheroid [45], [46], with a long-axis to short-axis ratio (α) fixed to 2, and was topped with a circular outlet and ellipsoidal inlet representing, respectively, the aortic valve (Ø 6.5 mm) and the mitral valve (equivalent Ø 8.0 mm). The geometry was subsequently meshed with ANSYS ICEM CFD, resulting in a tetrahedral mesh of 378 480 cells.…”

Section: A Computational Flow Phantommentioning

confidence: 99%

Assessing the Performance of Ultrafast Vector Flow Imaging in the Neonatal Heart via Multiphysics Modeling and <italic>In Vitro</italic> Experiments

Cauwenberge

Løvstakken²,

Fadnes³

et al. 2016

IEEE Trans. Ultrason., Ferroelect., Freq. Contr.

View full text Add to dashboard Cite

Section: A Computational Flow Phantommentioning

confidence: 99%

Assessing the Performance of Ultrafast Vector Flow Imaging in the Neonatal Heart via Multiphysics Modeling and <italic>In Vitro</italic> Experiments

Cauwenberge

Løvstakken²,

Fadnes³

et al. 2016

IEEE Trans. Ultrason., Ferroelect., Freq. Contr.

View full text Add to dashboard Cite

“…9, 25) of LV mechanics, focus was mainly on the influence of fiber architecture or electromechanical tissue behavior, assuming a normal LV shape based on gross anatomical measurements while limited attention was paid to the physiological interpretation of intramyocardial heterogeneity obtained. Therefore, the influence of LV shape on passive compliance and fiber stress and strain at end diastole (ED) was examined in a FE model in a previous study (12). It was found that the compliance did not alter significantly with LV shape while the intramyocardial distributions of passive fiber stress and strain depended on regional longitudinal curvature and wall thickness.…”

mentioning

confidence: 99%

“…In a study by Geerts et al (19), the influence of LV shape changes on transmural distributions of active fiber stress, as averaged over the ejection phase, and of sarcomere shortening was studied in ellipsoidal shape models but only at the equatorial level. Therefore, to investigate the influence of changes in LV shape on mechanical transmural distributions during systole in regional details, a computational FE study was performed using the LV shape models as developed by Choi et al (12). Hereto, simulations of passive filling followed by contraction was performed for different LV shapes, while keeping the material behavior, mechanical activation and contractility constant.…”

mentioning

confidence: 99%

Left-ventricular shape determines intramyocardial mechanical heterogeneity

Choi

Rademakers

Claus

2011

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

Choi HF, Rademakers FE, Claus P. Left-ventricular shape determines intramyocardial mechanical heterogeneity. Am J Physiol Heart Circ Physiol 301: H2351-H2361, 2011. First published September 23, 2011; doi:10.1152 doi:10. /ajpheart.00568.2011 remodeling is considered to be an important mechanism of disease progression leading to mechanical dysfunction of the heart. However, the interaction between the physiological changes in the remodeling process and the associated mechanical dysfunction is still poorly understood. Clinically, it has been observed that the left ventricle often undergoes large shape changes, but the importance of leftventricular shape as a contributing factor to alterations in mechanical function has not been clearly determined. Therefore, the interaction between left-ventricular shape and systolic mechanical function was examined in a computational finite-element study. Hereto, finiteelement models were constructed with varying shapes, ranging from an elongated ellipsoid to a sphere. A realistic transmural gradient in fiber orientation was considered. The passive myocardium was described by an incompressible hyperelastic material law with transverse isotropic symmetry. Activation was governed by the eikonaldiffusion equation. Contraction was incorporated using a Hill model. For each shape, simulations were performed in which passive filling was followed by isovolumic contraction and ejection. It was found that the intramyocardial distributions of fiber stress, strain, and stroke work density were shape dependent. Ejection performance was reduced with increasing sphericity, which was regionally related to a reduction in the active fiber stress development, fiber shortening, and stroke work in the midwall and subepicardial region at the midheight level in the left-ventricular wall. Based on these results, we conclude that a significant interaction exists between left-ventricular shape and regional myofiber mechanics, but the importance for left-ventricular remodeling requires further investigation. cardiac mechanics; cardiac muscle; systolic function; finite-element model; myocardial contractility REMODELING OF THE LEFT-VENTRICLE (LV) is a (patho)physiological process that frequently occurs to maintain cardiac homeostasis under changing myocardial loading conditions (22). Pathological LV remodeling can occur after myocardial infarction, in case of pressure overload due to aortic stenosis or hypertension, in myocarditis, in idiopathic dilated cardiomyopathy, or when volume overload occurs due to valvular regurgitation (18). Despite the different etiologies of these diseases, the occuring LV remodeling is controlled by common fundamental processes (29), which involve changes in cellular physiology, myocardial tissue structure, and LV shape. However, the interaction between the physiological changes observed in the remodeling process and the associated mechanical dysfunction is still poorly understood. Clinical evidence has shown that an increase in sphericity of LV shape correlates with a reduced s...

show abstract

“…Gjuvsland et al [41] argued that systems with monotone doseresponse relationships tend to produce more additive GP maps than unimodal or other non-monotone relationships. The low amount of interaction effects in figure 4 suggests that findings from earlier separate studies of stiffness [22], geometry [23] and fibre structure [24] will often remain valid under different conditions, including different genetic backgrounds and more complex and realistic genetic parameter variation. The details of the parameter-to-phenotype mapping will depend on the choice of constitutive law, as they use different parametrizations to capture different aspects of material behaviour.…”

Section: Genotype -Phenotype Map Features For Normal Versus Pathologimentioning

confidence: 99%

“…Specifically, we model the passive filling phase (late diastole) of the left ventricle, in which many individual factors have been studied previously [22][23][24][25]. The mechanics in this phase are relatively simple owing to the absence of active contraction, yet the strain and elastic energy stored in diastole gives our conclusions some relevance to the later phases of the heartbeat as well.…”

Section: Introductionmentioning

confidence: 99%

Towards causally cohesive genotype–phenotype modelling for characterization of the soft-tissue mechanics of the heart in normal and pathological geometries

Nordbø

Gjuvsland

Nermoen

et al. 2015

J. R. Soc. Interface.

View full text Add to dashboard Cite

A scientific understanding of individual variation is key to personalized medicine, integrating genotypic and phenotypic information via computational physiology. Genetic effects are often context-dependent, differing between genetic backgrounds or physiological states such as disease. Here, we analyse in silico genotype–phenotype maps (GP map) for a soft-tissue mechanics model of the passive inflation phase of the heartbeat, contrasting the effects of microstructural and other low-level parameters assumed to be genetically influenced, under normal, concentrically hypertrophic and eccentrically hypertrophic geometries. For a large number of parameter scenarios, representing mock genetic variation in low-level parameters, we computed phenotypes describing the deformation of the heart during inflation. The GP map was characterized by variance decompositions for each phenotype with respect to each parameter. As hypothesized, the concentric geometry allowed more low-level parameters to contribute to variation in shape phenotypes. In addition, the relative importance of overall stiffness and fibre stiffness differed between geometries. Otherwise, the GP map was largely similar for the different heart geometries, with little genetic interaction between the parameters included in this study. We argue that personalized medicine can benefit from a combination of causally cohesive genotype–phenotype modelling, and strategic phenotyping that captures effect modifiers not explicitly included in the mechanistic model.

show abstract

Influence of left-ventricular shape on passive filling properties and end-diastolic fiber stress and strain

Cited by 36 publications

References 23 publications

Assessing the Performance of Ultrafast Vector Flow Imaging in the Neonatal Heart via Multiphysics Modeling and <italic>In Vitro</italic> Experiments

Assessing the Performance of Ultrafast Vector Flow Imaging in the Neonatal Heart via Multiphysics Modeling and <italic>In Vitro</italic> Experiments

Left-ventricular shape determines intramyocardial mechanical heterogeneity

Towards causally cohesive genotype–phenotype modelling for characterization of the soft-tissue mechanics of the heart in normal and pathological geometries

Contact Info

Product

Resources

About