{"title":"A cavalpulmonary assist device utilising impedance pumping enhanced by peristaltic effect.","authors":"Arthur P Burns-Cox, Lian Gan, Ashraf W Khir","doi":"10.1177/03913988241268419","DOIUrl":"10.1177/03913988241268419","url":null,"abstract":"<p><strong>Background: </strong>Fontan procedure, the standard surgical palliation to treat children with single ventricular defects, causes systemic complications over years due to lack of pumping at cavopulmonary junction. A device developed specifically for cavopulmonary support is thus considered, while current commercial ventricular assist devices (VAD) induce high shear rates to blood, and have issues with paediatric suitability.</p><p><strong>Aim: </strong>To demonstrate the feasibility of a small, valveless, non-invasive to blood and pulsatile rotary pump, which integrates impedance and peristaltic effects.</p><p><strong>Methods: </strong>A prototype pump was designed and fabricated in-house without any effort to optimise its specification. It was then tested in vitro, in terms of effect of pumping frequency, background pressure differences and pump size on output performance.</p><p><strong>Results: </strong>Net flow rate (NFR) and maximum pressure head delivery are both reasonably linearly dependent on pumping frequency within normal physiological range. Positive linearity is also observed between NFR and the extent of asymmetric pumping. The device regulates NFR in favourable pressure head difference and overcomes significant adverse pressure head difference. Additionally, performance is shown to be insensitive to device size.</p><p><strong>Conclusions: </strong>The feasibility of the novel rotary pump integrating impedance and peristaltic effects is demonstrated to perform in normal physiological conditions without any optimisation effort. It provides promising results for possible future paediatric cavopulmonary support and warrants further investigation of miniaturisation and possible haemolysis.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11523539/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142107095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evaluation of the relationship between proximal upper-extremity arteriovenous fistula patency and atherogenic index of plasma.","authors":"Arda Aybars Pala, Yusuf Salim Urcun, Cengiz Guven","doi":"10.1177/03913988241269534","DOIUrl":"10.1177/03913988241269534","url":null,"abstract":"<p><strong>Background: </strong>The continuity of arteriovenous fistula (AVF) patency is essential for effective hemodialysis. In the present study, we aimed to investigate the relationship between AVF patency and atherogenic index of plasma (AIP) in patients with native proximal upper-extremity AVF.</p><p><strong>Methods: </strong>A total of 143 patients with native proximal upper-extremity AVF created in our clinic between January 2014 and April 2022 were analyzed retrospectively. Those with at least 24 months of follow-up and intact AVF were defined as \"Group 1\" (<i>n</i> = 97), and those with AVF thrombosis were defined as \"Group 2\" (<i>n</i> = 46).</p><p><strong>Results: </strong>The primary patency rates of the patient groups included in the study were found to be 88.1% at 6th month, 79% at 12th month, and 67.8% at 24th month. The mean AIP values that were calculated in Group 2 were found to be statistically significantly higher than the mean value calculated in Group 1 (0.30 ± 0.12 vs 0.20 ± 0.10, <i>p</i> < 0.001). In a multivariate logistic regression analysis made to identify the predictors of proximal upper-extremity AVF thrombosis development, total cholesterol (OR [odds ratio] = 2.259, 95% CI [confidence interval] = 1.468-3.475, <i>p</i> < 0.001), and triglyceride (OR = 13.777, 95% CI = 3.740-50.750, <i>p</i> < 0.001) were identified as independent predictors.</p><p><strong>Conclusion: </strong>A significant relationship was detected in the analyses between the easily calculated AIP values and the development of AVF thrombosis. The AIP is a remarkable preoperative parameter regarding proximal upper-extremity AVF patency.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142046634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Construction of a coagulation prediction model of the extracorporeal circulation circuit during hemodialysis with regional citrate anticoagulant (RCA).","authors":"Yanyan Gong, Menglin Zou, Laimin Luo","doi":"10.1177/03913988241269524","DOIUrl":"10.1177/03913988241269524","url":null,"abstract":"<p><strong>Objective: </strong>To construct a prediction model of coagulation in the extracorporeal circulation circuit during hemodialysis with regional citrate anticoagulant(RCA) conditions.</p><p><strong>Methods: </strong>This was a single-center, retrospective study. The clinical data of patients who received hemodialysis with RCA from February 2021 to March 2022 were collected. The risk predictors of coagulation in the extracorporeal circulation circuit were screened by LASSO regression. On this basis, we used multivariate logistic regression analysis to establish a nomogram prediction model.</p><p><strong>Results: </strong>A total of 98 patients received RCA hemodialysis for 362 times. Among them, 155 treatments with complete data were included in the study. Among the 155 treatments, coagulation of the extracorporeal circulation circuit occurred 12 times. The use of arteriovenous fistulas(AVF), the venous pressure at 4 h after hemodialysis initiation, blood flow velocity, dialyzer manufacturer, Systemic iCa<sup>2+</sup> at 1 h after hemodialysis initiation, plasma albumin level, and plasma d-dimer level were influencing factors of coagulation in the extracorporeal circuit during hemodialysis with RCA (<i>p</i> < 0.05). A nomogram model was made out of the above indicators. The area under the receiver operating characteristic (ROC) curve for predicting coagulation in the circuit was 0.967 (95% CI: 0.935-0.998). The internal validation result of the memory testing (bootstrap method) showed that the area under the ROC curve was 0.967 (95% CI: 0.918-0.991).</p><p><strong>Conclusion: </strong>The nomogram model has good discrimination and calibration and can intuitively and succinctly predict the risk of coagulation in the extracorporeal circulation circuit during hemodialysis with RCA.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142017344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tong Wu, Lei Han, Ye Zhu, Xiaojun Zeng, Yating Kang, Shuwen Zheng, Zhenhai Wang, Jianping Wang, Yonglin Gao
{"title":"Application of decalcified bone matrix in Salmon bone for tibial defect repair in rat model.","authors":"Tong Wu, Lei Han, Ye Zhu, Xiaojun Zeng, Yating Kang, Shuwen Zheng, Zhenhai Wang, Jianping Wang, Yonglin Gao","doi":"10.1177/03913988241269498","DOIUrl":"10.1177/03913988241269498","url":null,"abstract":"<p><strong>Aim: </strong>The optimal preparation conditions of Salmon decalcified bone matrix (S-DBM) were explored, and the properties of S-DBM bone particles and bone powder were studied respectively. The therapeutic effect of S-DBM on tibial defect in female Sprague Dawley (SD) rats was preliminarily verified.</p><p><strong>Methods: </strong>This study assessed the structural and functional similarities of Salmon bone DBM (S-DBM). The biocompatibility assessment was conducted using both in vivo and in vitro experiments, establishing an animal model featuring tibial defects in rats and on the L929 cell line, respectively. The control group, bovine DBM (bDBM), was compared to the S-DBM-treated tibial defect rats. Imaging and histology were used to study implant material changes, defect healing, osteoinductive repair, and degradation.</p><p><strong>Results: </strong>The findings of our study indicate that S-DBM exhibits favorable repairing effects on bone defects, along with desirable physicochemical characteristics, safety, and osteogenic activity.</p><p><strong>Conclusions: </strong>The S-DBM holds significant potential as a medical biomaterial for treating bone defects, effectively fulfilling the clinical demands for materials used in bone tissue repair engineering.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142017343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Flexible inner surface of polysulfone membranes prevents platelet adhesive protein adsorption and improves antithrombogenicity in vitro.","authors":"Ryo Takatsuji, Masahide Koremoto, Yoko Fujimoto, Yuko Saida, Yoshihiro Hatanaka","doi":"10.1177/03913988241269465","DOIUrl":"10.1177/03913988241269465","url":null,"abstract":"<p><strong>Background: </strong>We investigated whether the condition of the inner surface of hollow fibers affects the blood compatibility of hemodialyzers.</p><p><strong>Methods: </strong>We used scanning probe microscope/atomic force microscopy (SPM/AFM) to investigate the height of the swelling and flexible layers (thickness and softness) on the inner surfaces of the hollow fibers. Next, we tested the blood compatibility between dialyzers comprising a hollow fiber membrane, in which the other dialyzers, except for PVP, were additionally coated using PS membranes coated with other materials. After blood was injected into the dialyzer and plugged, dynamic stimulation was performed by slightly rotating the dialyzer for 4 h, although there was no blood circulation.</p><p><strong>Results: </strong>The vitamin E-coated polysulfone (PS) membrane showed a higher thickness and softness of the flexible layer than the asymmetric cellulose triacetate membrane without polyvinylpyrrolidone (PVP) and the PS membranes with PVP. We found that the dialyzer with vitamin E coating significantly suppressed the decrease in platelets, increase in β-TG, and increase in PF4 compared to those coated with NV polymer. Additionally, as the adsorbed protein on the inner surface, the total protein, fibronectin, and vWF levels were significantly lower in the vitamin E-coated dialyzer.</p><p><strong>Conclusion: </strong>The thickness and softness of the flexible layer of the inner surface of the hollow fiber membrane in vitro affect differences in blood coagulation performance in clinical research. Future clinical trials are required to confirm our results.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142125664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stefanie Broszeit, Joachim Kron, Til Leimbach, John Volkenandt, Susanne Kron
{"title":"Vascular refilling in hemodialysis using feedback-controlled ultrafiltration profile.","authors":"Stefanie Broszeit, Joachim Kron, Til Leimbach, John Volkenandt, Susanne Kron","doi":"10.1177/03913988241264709","DOIUrl":"10.1177/03913988241264709","url":null,"abstract":"<p><strong>Background: </strong>The rate and the duration of ultrafiltration (UF) are considered the most important factors to affect vascular refilling. The aim of the study was to investigate whether a UF profile could improve the vascular refilling.</p><p><strong>Methods: </strong>Dialysis was delivered by a machine providing feedback control of ultrafiltration rates. Absolute blood volume (BV) was measured by dialysate bolus method. Vascular refilling volume (<i>V</i><sub>ref</sub>) was calculated as UF volume - Δ absolute BV.</p><p><strong>Results: </strong>In 40 patients, refilling fraction (<i>V</i><sub>ref</sub>/UF volume) was 30.5% in the first hour. Thereafter, refilling fraction steeply increased and reached maximum values in the third and fourth hour at about 95%. The cumulative refilling fraction was 68.5 ± 9.4% at the end. In 14 patients, refilling data from the feedback-controlled UF profile were compared to dialysis sessions with constant UF rates. In 12 of 14 patients, refilling fraction was significantly (<i>p</i> = 0.013) higher in sessions with UF profile (71.6% vs 64.4%).There was a significant negative correlation (<i>r</i> = -0.606; <i>p</i> = 0.002) between the blood volume to extracellular volume ratio and the refilling fraction. The sum of this ratio and the refilling fraction was 1.01 ± 0.06.</p><p><strong>Conclusions: </strong>Despite significant differences, a feedback-controlled UF profile has no advantage over the previous refilling studies with regard to the refilling fraction because vascular refilling seems to depend mainly on the ratio of BV to ECV. This would explain the different results in studies using BV guided UF feedback programs.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141889126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
John K Leypoldt, Mauro Pietribiasi, Malgorzata Debowska, Monika Wieliczko, Malgorzata Twardowska-Kawalec, Jolanta Malyszko, Jacek Waniewski
{"title":"Evaluating hydrogen ion mobilization during hemodialysis using only predialysis and postdialysis blood bicarbonate concentrations.","authors":"John K Leypoldt, Mauro Pietribiasi, Malgorzata Debowska, Monika Wieliczko, Malgorzata Twardowska-Kawalec, Jolanta Malyszko, Jacek Waniewski","doi":"10.1177/03913988241268026","DOIUrl":"10.1177/03913988241268026","url":null,"abstract":"<p><strong>Introduction: </strong>The hydrogen ion (H<sup>+</sup>) mobilization model has been previously shown to provide a quantitative description of intradialytic changes in blood bicarbonate (HCO<sub>3</sub>) concentration during hemodialysis (HD). The current study evaluated the accuracy of different methods for estimating the H<sup>+</sup> mobilization parameter (H<sub>m</sub>) from this model.</p><p><strong>Methods: </strong>The study compared estimates of the H<sup>+</sup> mobilization parameter using predialysis, hourly during the HD treatment, and postdialysis blood HCO<sub>3</sub> concentrations (H<sub>m</sub>-full2) with those determined using only predialysis and postdialysis blood HCO<sub>3</sub> concentrations assuming steady state conditions (H<sub>m</sub>-SS2) during the midweek treatment in 24 chronic HD patients treated thrice weekly.</p><p><strong>Results: </strong>Estimated H<sub>m</sub>-full2 values (0.163 ± 0.079 L/min [mean ± standard deviation]) were higher than, but not statistically different (<i>p</i> = 0.067) from, those of H<sub>m</sub>-SS2 (0.152 ± 0.065 L/min); the values of H<sub>m</sub>-full2 and H<sub>m</sub>-SS2 were highly correlated with a correlation coefficient of 0.948 and a mean difference that was small (0.011 L/min). Further, the H<sup>+</sup> mobilization parameter values calculated using only predialysis and postdialysis blood HCO<sub>3</sub> concentrations during the first and third HD treatments of the week were not different from those calculated during the midweek treatment.</p><p><strong>Conclusions: </strong>The H<sup>+</sup> mobilization model can be used to provide estimates of the H<sup>+</sup> mobilization parameter without the need to measure hourly intradialytic blood HCO<sub>3</sub> concentrations.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141987865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maria Kislikova, Almudena Vega, Eduardo Verde, Soraya Abad, Marco Vaca, Adriana Acosta, Angela González, Arturo Bascuñana, Antonia Mijailova, Coraima Nava, Miguel Villa, Juan Carlos Ruiz, Marian Goicoechea
{"title":"Depurative capacity toward medium molecules of the dialyzer Toray NV-U<sup>®</sup> Hydrolink™: A new hydrophilic membrane to perform online hemodiafiltration.","authors":"Maria Kislikova, Almudena Vega, Eduardo Verde, Soraya Abad, Marco Vaca, Adriana Acosta, Angela González, Arturo Bascuñana, Antonia Mijailova, Coraima Nava, Miguel Villa, Juan Carlos Ruiz, Marian Goicoechea","doi":"10.1177/03913988241274735","DOIUrl":"https://doi.org/10.1177/03913988241274735","url":null,"abstract":"<p><strong>Introduction: </strong>New dialysis membranes with new properties are being developed to improve efficacy and tolerance. The hemocompatibility of a polymeric biomaterial is influenced by the layer of water at the blood membrane interface. The new dialyzer TORAY NV-U<sup>®</sup> has a membrane Hydrolink™, designed to suppress platelet adhesion and to improve the hemocompatibility. Until now, there is no experience in online hemodiafiltration (OL-HDF).The objective of the present study is to evaluate the efficacy of this new membrane in OL-HDF therapy compared to another membrane commonly used. Other objectives are to evaluate the inflammatory response, hemodynamic tolerance, and the anticoagulation regimes.</p><p><strong>Methods: </strong>This is a prospective pilot study performed in five anuric patients receiving OL-HDF. For 1 month patients were kept with their usual dialyzer FX1000<sup>®</sup> (FMC). Subsequently, the dialyzer was changed to TORAY NV-U<sup>®</sup> (Hydrolink<sup>®</sup>) for 1 month. In the last dialysis session of each dialyzer, blood tests were performed to evaluate inflammation and depurative capacity.</p><p><strong>Results: </strong>We did not find differences in medium size removal molecules and convective volume: FX1000<sup>®</sup>: 31 ± 9 l per session and Hydrolink™ 30 ± 8 l; <i>p</i> = 0.7); β2microglobulin reduction ratio (RR) FX1000<sup>®</sup> FMC 83 ± 3%; Hydrolink™ 79 ± 4; <i>p</i> = 0.14; Myoglobin RR FX1000<sup>®</sup> FMC 72 ± 7%; Hydrolink™ 76 ± 4; <i>p</i> = 0.28. We did not find differences in inflammation parameters: serum IL6 with FX1000<sup>®</sup> 6.0 ± 4.2 pg/mL; Hydrolink™ 7.6 ± 5.0 pg/mL; <i>p</i> = 0.3.During all sessions with the two dialyzers there was adequate plasmatic filling, reaching 85 % filling. All patients had \"good\" dialyzer status in all dialysis sessions with TORAY NV-U<sup>®</sup>, while the dialyzer status with FX1000<sup>®</sup> was \"good\" in 20% of the sessions, \"medium\" in 30%, and \"dirty\" in the remaining 50% dialysis sessions.</p><p><strong>Conclusions: </strong>The new dialyzer Hydrolink™, TORAY NV-U<sup>®</sup> is not inferior to perform OL-HDF compared to dialyzers usually used for this therapy, and could allow decrease heparin doses. Further studies with a bigger sample size and longer follow-up will answer if Hydrolink improves inflammation and assess a better hemodynamic tolerance.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142286391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jesús Emilio Barrueco-Francioni, María Carmen Martínez-González, Juan Francisco Martínez-Carmona, María Palma Benítez-Moreno, Cesar Aragón-González, Manuel Enrique Herrera-Gutiérrez
{"title":"ECMO in severe hypoxemia post liver transplant for hepatopulmonary syndrome.","authors":"Jesús Emilio Barrueco-Francioni, María Carmen Martínez-González, Juan Francisco Martínez-Carmona, María Palma Benítez-Moreno, Cesar Aragón-González, Manuel Enrique Herrera-Gutiérrez","doi":"10.1177/03913988241274252","DOIUrl":"https://doi.org/10.1177/03913988241274252","url":null,"abstract":"<p><p>Hepatopulmonary syndrome (HPS) poses a significant challenge in liver transplant patients, affecting between 10% and 30% of candidates. Historically, HPS was considered a contraindication for liver transplantation due to its association with high mortality rates. However, recent studies have shown improvements in pulmonary function post-transplant, leading to the inclusion of these patients as candidates. Despite this progress, approximately one-fifth of liver transplant recipients develop severe postoperative hypoxia, further complicating their clinical course and contributing to increased mortality. The management of post-transplant HPS involves various strategies, including extracorporeal membrane oxygenation (ECMO), although its use remains infrequently reported. Theoretical models suggest that oxygenation typically improves within 10 days post-transplant, while resolution of HPS may take 6-12 months, making ECMO an attractive possibility as a bridge to recovery in this population. We present a case were ECMO was used in this context.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142107096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An analytic method to investigate hemodynamics of the cardiovascular system: Biventricular system.","authors":"Yuxin Zhu, Xu Mei, Wanning Ge, Tingting Wu, Liudi Zhang, Polin Hsu","doi":"10.1177/03913988241260943","DOIUrl":"10.1177/03913988241260943","url":null,"abstract":"<p><p>Previously, we found analytic solutions for single ventricular system based on the lumped parameter model (LPM). In this study, we generalized the method to biventricular system and derived its analytic solutions. LPM is just a set of differential equations, but it is difficult to solve due to time-varying ventricular elastance and high order. Mathematically, there exist no elementary solutions for time-varying equations. It turns out that instead of differential equations, according to volume conservation, a set of algebraic equations can be carried out. The solutions of the set of equations are just physiological states at end of systolic and diastolic phases such as end systolic/diastolic pressure/volume of left ventricle. As a preliminary application, the method is utilized to deduce the hemodynamic effects of VA ECMO. Left ventricular (LV) distension, a serious complication of VA ECMO, is usually attributed to factors such as increased afterload, inadequate LV unloading, reduced myocardial contractility or aortic valve regurgitation (AR), bronchial and Thebesian return in the absence of aortic valve (AoV) opening. Among these, reduced contractility and AR are strongly associated with LV distension. However, in the absence of reduced contractility or AR, it is less clear whether increased afterload or inadequate LV unloading alone can cause LV distension. This leads to the critical question: under what conditions does LV distension occur in the absence of reduced contractility or AR? The analytic formulas derived in this study give conditions for LV distension. Furthermore, the results show that the analytic hemodynamics are coincident with simulated results.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141901691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}