Biomechanical and Hemodynamic Measures of Right Ventricular Diastolic Function: Translating Tissue Biomechanics to Clinical Relevance

Jang, Sae; Vanderpool, Rebecca; Avazmohammadi, Reza; Lapshin, Eugene; Bachman, Timothy N.; Sacks, Michael S.; Simon, Marc A.

doi:10.1161/jaha.117.006084

Cited by 43 publications

(61 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The qualitative contribution of myofibers and (perymysial) collagen fibers remained unchanged in the PAH tissues such that the behavior of the RVFW was still governed by myofiber response alone in the low strain regime, 33 and collagen fibers and their interaction with myofibers began to gradually contribute to the behavior as their recruitment proceeded (Fig. 6).…”

Section: Resultsmentioning

confidence: 98%

Transmural remodeling of right ventricular myocardium in response to pulmonary arterial hypertension

et al. 2017

Self Cite

View full text Add to dashboard Cite

Pulmonary arterial hypertension (PAH) imposes substantial pressure overload on the right ventricular free wall (RVFW), leading to myofiber hypertrophy and remodeling of its collagen fiber architecture. The transmural nature of these adaptations and their effects on the macroscopic mechanical behavior of the RVFW remain largely unexplored. In the present work, we extended our constitutive model for RVFW myocardium to investigate the transmural mechanical and structural remodeling post-PAH. Recent murine experimental studies provided us with comprehensive histomorphological and biaxial mechanical data for viable, passive myocardium for normal and post hypertensive cases. Multiple fiber-level remodeling events were found to be localized in the midwall region (40% < depth < 60%): (i) reorientation and alignment of both myo- and collagen fibers towards longitudinal (apex-to-outflow tract) direction, (ii) substantial increase in the rate of the recruitment of collagen fibers with strain, and (iii) a corresponding increase in the mechanical interactions between the collagen and myofibers. These adaptations suggest a denser and more fibrous connective tissue in the midwall region, and led to a substantially stiffer mechanical response along the longitudinal direction in post-PAH tissues. Moreover, using a Laplace-type mechanical equilibrium analysis of the right ventricle to approximate the wall stress state, we estimated that the longitudinal component of stress remained higher in the hypertensive state while the circumferential component approximately maintained homeostasis values. This result was consistent with our observation from the fiber- and tissue-level remodeling that longitudinally oriented collagen fibers, localized in the midwall region, dominated the remodeling process. The findings of this study highlight the need for more integrated cellular-tissue-organ analysis to better understand the remodeling events during PAH and design interventions.

show abstract

Section: Resultsmentioning

confidence: 98%

Transmural remodeling of right ventricular myocardium in response to pulmonary arterial hypertension

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…Uniaxial and biaxial mechanical tests are the most common methods to investigate the ventricular mechanical property after tissue harvest (Figure 3). While the uniaxial mechanical test offers a quicker and easier examination of the material mechanical property, the biaxial mechanical test better mimics the in vivo loading conditions and provides more comprehensive measurements of the anisotropic mechanical behavior [17,19,20,22,[39][40][41]. Both methods have been used in prior studies of LV and RV mechanical properties [17,20,[22][23][24][25][26][27][28][29][30][39][40][41][42][43][44][45][46] (please see Table 1 for a summary of these studies).…”

Section: Uniaxial and Biaxial Tensile Mechanical Testsmentioning

confidence: 99%

“…The characterization of the anisotropic behavior of ventricles is highly dependent on the definition of the biaxial coordinate system. To date, there are two main types of coordinate systems: the main fiber and cross-fiber coordinate system [17,30,44], and the outflow tract and cross-outflow tract coordinate system [20,29,40]. Using the former coordinate system, it is consistently observed that the tissue behaves stiffer in the fiber direction compared with the cross-fiber direction [22].…”

Section: Anisotropic Behavior Of Ventriclesmentioning

confidence: 99%

“…Using non-invasive echocardiography, reduced RV longitudinal strains have been reported in pre-capillary PH (pulmonary arterial hypertension) patients and PH patients with other etiologies [128][129][130]. Increased RV stiffness was frequently reported in the preclinical studies of PH via the ex vivo tissue mechanical tests [20,29,40]. However, the impact of RV stiffening in the ventricular performance is rarely investigated.…”

Section: Significance Of Ventricular Stiffening In Heart Failurementioning

confidence: 99%

“…It is generally accepted that the mechanical property of the myocardium is an important determinant of the ventricular function [19,20]. Indeed, changes in the ventricular mechanical properties during the HF progression have been reported in numerous studies for both LVs and RVs.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Current Understanding of the Biomechanics of Ventricular Tissues in Heart Failure

Liu

Wang

2019

Bioengineering

View full text Add to dashboard Cite

Heart failure is the leading cause of death worldwide, and the most common cause of heart failure is ventricular dysfunction. It is well known that the ventricles are anisotropic and viscoelastic tissues and their mechanical properties change in diseased states. The tissue mechanical behavior is an important determinant of the function of ventricles. The aim of this paper is to review the current understanding of the biomechanics of ventricular tissues as well as the clinical significance. We present the common methods of the mechanical measurement of ventricles, the known ventricular mechanical properties including the viscoelasticity of the tissue, the existing computational models, and the clinical relevance of the ventricular mechanical properties. Lastly, we suggest some future research directions to elucidate the roles of the ventricular biomechanics in the ventricular dysfunction to inspire new therapies for heart failure patients.

show abstract

RVEX: Right Ventricular External Device for Biomimetic Support and Monitoring of the Right Heart

Pirozzi

Kight

Shad

et al. 2022

Adv Materials Technologies

View full text Add to dashboard Cite

devices (LVADs) have provided an invaluable alternative for thousands of patients with severe left-sided heart failure. Nevertheless, right ventricular failure is a leading cause of death and morbidity following several cardiothoracic procedures, including implantation of LVAD devices. [1,2] According to Lampert et al., postoperative right ventricular failure, defined as the inability of the right ventricle to maintain enough blood flow through the pulmonary circulation, remains the most frequent and serious complication after LVAD implantation and occurs in up to 35% of LVAD recipients, especially in patients with smaller left ventricular size, such as women. [2][3][4] LVAD implantation requires the right ventricle (RV) to increase its output flow in order to match the LVAD flow, a concept referred to in medical jargon as "hemodynamic adaptation." [5] It is worth noting that failure to adapt to the new hemodynamic requirements manifests acutely in the first few days or weeks following surgical procedures. [5] Limiting LVAD patient selection based on predictive models is an attractive option, but preoperative risk factors of RV failure in LVAD patients are inconsistent and newer deep-learning methods to predict postoperative RV failure have yet to be tested in prospective trials. [6,7] Thus, clinical strategies and devices should be designed to provide adequate protection to the RV and support its adaptation to the new hemodynamic demand. In this context, continuous monitoring over the days following the surgery would be an effective way to track and adjust treatment response.Failure to adapt to new hemodynamic demand can put the RV at a biomechanical disadvantage, characterized by strain concentrations that trigger adverse dilatation (or "remodeling") and, eventually, failure. It has been shown that such dilatation is a well-recognized precursor of heart failure, and is driven by biomechanical perturbations in the passive filling phase of the heart's cycle, such as excessive tissue stresses or strains due to overfilling of the ventricle. [8,9] Previous attempts at mechanically reducing ventricular strain through devices have been referred to as ventricular restraint therapy: a non-transplant surgical treatment mainly investigated in the context of the left ventricular dilation. This strategy was attempted in patients where the left ventricle (LV) had experienced significant dilatation, in an attempt to prevent failure. To limit undesired tissue distention and expansion, the epicardial (outer-most) layer of the heart Right ventricular (RV) failure remains a significant burden for patients with advanced heart failure, especially after major cardiac surgeries such as implantation of left ventricular assist devices. Device solutions that can assist the complex biological function of heart muscle without the disadvantages of bulky designs and infection-prone drivelines remain an area of pressing clinical need, especially for the right ventricle. In addition, devices that incur contact between blood and artificial sur...

show abstract

Biomechanical and Hemodynamic Measures of Right Ventricular Diastolic Function: Translating Tissue Biomechanics to Clinical Relevance

Cited by 43 publications

References 37 publications

Transmural remodeling of right ventricular myocardium in response to pulmonary arterial hypertension

Transmural remodeling of right ventricular myocardium in response to pulmonary arterial hypertension

Current Understanding of the Biomechanics of Ventricular Tissues in Heart Failure

RVEX: Right Ventricular External Device for Biomimetic Support and Monitoring of the Right Heart

Contact Info

Product

Resources

About