Closed-Loop Lumped Parameter Modeling of Hemodynamics During Cirrhogenesis in Rats

Audebert, Chloé; Peeters, Geert; Segers, Patrick; Laleman, Wim; Monbaliu, Diethard; Korf, Hannelie; Trebicka, Jonel; Vignon-Clementel, Irene E.; Debbaut, Charlotte

doi:10.1109/tbme.2018.2793948

Cited by 15 publications

(6 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A lumped model with the hepatic artery, portal vein, and hepatic vein was developed, and the predicted hepatic arterial pressure and blood flow rates were computed at different percentages of hepatectomy, and the findings were subsequently supported by the results upon experiments on pigs. 24 Lumped models have been employed in the study of hepatic circulation after partial hepatectomy 25 or liver diseases 26 in rats. Nevertheless, few computational models included all hepatic vessels to study and understand the physiology of the hepatic system in human subjects.…”

mentioning

confidence: 99%

Anatomically based simulation of hepatic perfusion in the human liver

Hunter

Cousins³

et al. 2019

Numer Methods Biomed Eng

View full text Add to dashboard Cite

Liver structures of a healthy subject are digitised and segmented from computed tomography (CT) images, and hepatic perfusion is modelled in the hepatic artery and portal vein of the healthy subject with structured tree‐based outflow boundary conditions. This self‐similar structured tree is widely used in the literature, eg, blood flow simulation in larger systemic arteries and cerebral circulation, and is used in this study to model the effect of the smaller hepatic arteries and arterioles, as well as the smaller hepatic portal veins and portal venules. Physiologically reasonable results are obtained. Since the structured tree terminates at the size of the microvasculature system in liver lobules, the structured tree boundary condition will enable the proposed organ‐level model of hepatic arterial flow to be easily connected to tissue‐level models of liver lobules. Blood flow in the hepatic vein is also modelled in this subject with three‐element Windkessel model as outflow boundary conditions. The benefit of integrating the perfusion in all hepatic vascular vessels is that it helps us analyse some complicated clinical phenomenon more efficiently, eg, one possible application is to obtain the portal pressure gradient (PPG) to help examine the reliability of hepatic venous pressure gradient (HVPG) as an indirect measure of portal pressure. Moreover, since four to six generations of hepatic vessels, which are sufficient for liver classification analysis, were employed in the model, this study is setting the computational foundation of a potentially handy surgical tool.

show abstract

mentioning

confidence: 99%

Anatomically based simulation of hepatic perfusion in the human liver

Hunter

Cousins³

et al. 2019

Numer Methods Biomed Eng

View full text Add to dashboard Cite

show abstract

“…Clinical measurements of blood pressure, volume, and flows were acquired at the beginning, middle, and end of the intervention period to detect potentially non-linear parameter changes. This study, similarly to the work of [16], investigates the change of parameters throughout an intervention period, which could give more insight into progression of disease or therapy. However, Audebert et al focus on a parameter in response to disease progression in rats, while we monitor exercise as hypertension therapy in humans.…”

Section: Introductionmentioning

confidence: 99%

“…Fig 16. The model-optimized pressure curve based on the mean of the best parameter estimates for the individual is shown with the raw data to which it is optimized for a participant.…”

mentioning

confidence: 99%

Monitoring variability in parameter estimates for lumped parameter models of the systemic circulation using longitudinal hemodynamic measurements

et al. 2023

View full text Add to dashboard Cite

Background Physics-based cardiovascular models are only recently being considered for disease diagnosis or prognosis in clinical settings. These models depend on parameters representing the physical and physiological properties of the modeled system. Personalizing these parameters may give insight into the specific state of the individual and etiology of disease. We applied a relatively fast model optimization scheme based on common local optimization methods to two model formulations of the left ventricle and systemic circulation. One closed-loop model and one open-loop model were applied. Intermittently collected hemodynamic data from an exercise motivation study were used to personalize these models for data from 25 participants. The hemodynamic data were collected for each participant at the start, middle and end of the trial. We constructed two data sets for the participants, both consisting of systolic and diastolic brachial pressure, stroke volume, and left-ventricular outflow tract velocity traces paired with either the finger arterial pressure waveform or the carotid pressure waveform. Results We examined the feasibility of separating parameter estimates for the individual from population estimates by assessing the variability of estimates using the interquartile range. We found that the estimated parameter values were similar for the two model formulations, but that the systemic arterial compliance was significantly different ($$p < 10^{-6}$$ p < 10 - 6 ) depending on choice of pressure waveform. The estimates of systemic arterial compliance were on average higher when using the finger artery pressure waveform as compared to the carotid waveform. Conclusions We found that for the majority of participants, the variability of parameter estimates for a given participant on any measurement day was lower than the variability both across all measurement days combined for one participant, and for the population. This indicates that it is possible to identify individuals from the population, and that we can distinguish different measurement days for the individual participant by parameter values using the presented optimization method.

show abstract

“…Given the fact that in vivo measurement of the details of blood flow patterns and high-precision quantification of hemodynamic parameters (e.g., WSS) in the PVS remain challenging in the clinical settings, computational hemodynamics modeling may serve as an alternative approach. In the literature, computational models have been widely used to address hemodynamic problems related to the diagnosis of portal hypertension (Wang et al, 2017(Wang et al, , 2018(Wang et al, , 2020, the pathogenesis or surgical treatment of liver diseases (Ho et al, 2013;Peeters et al, 2015;Audebert et al, 2018;Golse et al, 2020), or the presence of thrombus in the PVS (Petkova et al, 2003;Wang et al, 2014;Zhou et al, 2015;Aktar and Islam, 2017), but no models have been applied to address the hemodynamic impacts of splenectomy. In the present study, we built computational models to simulate hemodynamics in the PVS before and after splenectomy.…”

Section: Introductionmentioning

confidence: 99%

Influences of Anatomorphological Features of the Portal Venous System on Postsplenectomy Hemodynamic Characteristics in Patients With Portal Hypertension: A Computational Model-Based Study

2021

View full text Add to dashboard Cite

Splenectomy, as an effective surgery for relieving complications caused by portal hypertension, is often accompanied by a significantly increased incidence of postoperative thrombosis in the portal venous system (PVS). While the underlying mechanisms remain insufficiently understood, the marked changes in hemodynamic conditions in the PVS following splenectomy have been suggested to be a potential contributing factor. The aim of this study was to investigate the influences of the anatomorphological features of the PVS on hemodynamic characteristics before and after splenectomy, with emphasis on identifying the specific anatomorphological features that make postoperative hemodynamic conditions more clot-promoting. For this purpose, idealized computational hemodynamics models of the PVS were constructed based on general anatomical structures and population-averaged geometrical parameters of the PVS. In the models, we incorporated various anatomorphological variations to represent inter-patient variability. The analyses of hemodynamic data were focused on the spatial distribution of wall shear stress (WSS) and the area ratio of wall regions exposed to low WSS (ALS). Obtained results showed that preoperative hemodynamic conditions were comparable among different models in terms of space-averaged WSS and ALS (all were small) irrespective of the considerable differences in spatial distribution of WSS, whereas, the inter-model differences in ALS were significantly augmented after splenectomy, with the value of ALS reaching up to over 30% in some models, while being smaller than 15% in some other models. Postoperative ALS was mainly determined by the anatomical structure of the PVS, followed by some morphogeometrical parameters, such as the diameter and curvature of the splenic vein, and the distance between the inferior mesenteric vein and splenoportal junction. Relatively, the angles between tributary veins and trunk veins only had mild influences on ALS. In addition, a marked increase in blood viscosity was predicted after splenectomy, especially in regions with low WSS, which may play an additive role to low WSS in initiating thrombosis. These findings suggest that the anatomical structure and some morphogeometrical features of the PVS are important determinants of hemodynamic conditions following splenectomy, which may provide useful clues to assessing the risk of postsplenectomy thrombosis based on medical imaging data.

show abstract

Closed-Loop Lumped Parameter Modeling of Hemodynamics During Cirrhogenesis in Rats

Cited by 15 publications

References 51 publications

Anatomically based simulation of hepatic perfusion in the human liver

Anatomically based simulation of hepatic perfusion in the human liver

Monitoring variability in parameter estimates for lumped parameter models of the systemic circulation using longitudinal hemodynamic measurements

Influences of Anatomorphological Features of the Portal Venous System on Postsplenectomy Hemodynamic Characteristics in Patients With Portal Hypertension: A Computational Model-Based Study

Contact Info

Product

Resources

About