Cardiovascular Engineering and Technology最新文献

{"title":"Activation of a Soft Robotic Left Ventricular Phantom Embedded in a Closed-Loop Cardiovascular Simulator: A Computational and Experimental Analysis.","authors":"Nele Demeersseman, Maria Rocchi, Heleen Fehervary, Guillermo Fernández Collazo, Bart Meyns, Libera Fresiello, Nele Famaey","doi":"10.1007/s13239-024-00755-w","DOIUrl":"10.1007/s13239-024-00755-w","url":null,"abstract":"<p><strong>Purpose: </strong>Cardiovascular simulators are used in the preclinical testing phase of medical devices. Their reliability increases the more they resemble clinically relevant scenarios. In this study, a physiologically actuated soft robotic left ventricle (SRLV) embedded in a hybrid (in silico- in vitro) simulator of the cardiovascular system is presented, along with its experimental and computational analysis.</p><p><strong>Methods: </strong>A SRLV phantom, developed from a patient's CT scan using polyvinyl alcohol (PVA), is embedded in a hybrid cardiovascular simulator. We present an activation method in which the hydraulic pressure external ( <math> <mrow><msub><mi>P</mi> <mi>e</mi></msub> <mrow><mo>(</mo> <mi>t</mi> <mo>)</mo></mrow> </mrow> </math> ) to the SRLV is continuously adapted to regulate the left ventricular volume ( <math> <mrow><msub><mi>V</mi> <mi>i</mi></msub> <mrow><mo>(</mo> <mi>t</mi> <mo>)</mo></mrow> </mrow> </math> ), considering the geometry and material behavior of the SRLV and the left ventricular pressure ( <math> <mrow><msub><mi>P</mi> <mi>i</mi></msub> <mrow><mo>(</mo> <mi>t</mi> <mo>)</mo></mrow> </mrow> </math> ). This activation method is verified using a finite element (FE) model of the SRLV and validated in the hybrid simulator. Different hemodynamic profiles are presented to test the flexibility of the method.</p><p><strong>Results: </strong>Both the FE model and hybrid simulator could represent the desired in silico data ( <math> <mrow><msub><mi>P</mi> <mi>i</mi></msub> <mrow><mo>(</mo> <mi>t</mi> <mo>)</mo></mrow> </mrow> </math> , <math> <mrow><msub><mi>V</mi> <mi>i</mi></msub> <mrow><mo>(</mo> <mi>t</mi> <mo>)</mo></mrow> </mrow> </math> ) with the implemented activation method, with deviations below 8.09% in the FE model and mainly < 10% errors in the hybrid simulator. Only two measurements out of 32 exceeded the 10% threshold due to simulator setup limitations.</p><p><strong>Conclusion: </strong>The activation method effectively allows to represent various pressure-volume loops, as verified numerically, and validated experimentally in the hybrid simulator. This work presents a high-fidelity platform designed to simulate cardiovascular conditions, offering a robust foundation for future testing of cardiovascular medical devices under physiological conditions.</p>","PeriodicalId":54322,"journal":{"name":"Cardiovascular Engineering and Technology","volume":" ","pages":"34-51"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142480770","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":"Insights from Computational Fluid Dynamics and In Vitro Studies for Stent Protrusion in Iliac Vein: How Far Shall We Go?","authors":"Zhenmin Fan, Jian Lu, Hao Cheng, Xia Ye, Xiaoyan Deng, Pengfei Zhao, Junjun Liu, Mingyuan Liu","doi":"10.1007/s13239-024-00758-7","DOIUrl":"10.1007/s13239-024-00758-7","url":null,"abstract":"<p><p>These findings provide significant implications for the enhancement of iliac vein stent implantation strategies and stent design. The prevalent use of stents for treating Iliac Vein Compression Syndrome (IVCS) has shown efficacy, yet the associated clinical adverse events, including stent restenosis and postoperative thrombosis, are significant concerns. Up to now, the mechanism how the stent implantation induces the restenosis and DVT is still unclear. Our study hypothesizes that these adverse outcomes arise from altered blood flow dynamics following stent implantation. Employing computational modeling and medical imaging, we simulated IVCS after various stenting procedures to assess their impact on venous blood flow characteristics, including wall shear stress (WSS), residence time (RRT), and oscillatory shear index (OSI). Our findings reveal that a stent protruding into the vena cava impedes blood circulation, with increased protrusion exacerbating this obstruction. This is particularly evident at the vein bifurcation, where low WSS and elevated OSI and RRT are observed. Moreover, a higher stent strut density further obstructs blood flow, deteriorating the hemodynamic environment. Consequently, stent protrusion into the vena cava can enhance the likelihood of adverse post-surgical events. These insights have profound implications for optimizing iliac vein stent implantation techniques and stent design.</p>","PeriodicalId":54322,"journal":{"name":"Cardiovascular Engineering and Technology","volume":" ","pages":"79-90"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632604","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":"On the Relative Effects of Wall and Intraluminal Thrombus Constitutive Material Properties in Abdominal Aortic Aneurysm Wall Stress.","authors":"Vivian Reyna, Niusha Fathesami, Wei Wu, Satish C Muluk, Victor De Oliveira, Ender A Finol","doi":"10.1007/s13239-024-00757-8","DOIUrl":"10.1007/s13239-024-00757-8","url":null,"abstract":"<p><strong>Introduction: </strong>An abdominal aortic aneurysm (AAA) is a dilation localized in the infrarenal segment of the abdominal aorta that can expand continuously and rupture if left untreated. Computational methods such as finite element analysis (FEA) are widely used with in silico models to calculate biomechanical predictors of rupture risk while choosing constitutive material properties for the AAA wall and intraluminal thrombus (ILT).</p><p><strong>Methods: </strong>In the present work, we investigated the effect of different constitutive material properties for the wall and ILT on 21 idealized and 10 unruptured patient-specific AAA geometries. Three material properties were used to characterize the wall and two for the ILT, leading to six material model combinations for each AAA geometry subject to appropriate boundary conditions.</p><p><strong>Results: </strong>The results of the FEA simulations indicate significant differences in the average peak wall stress (PWS), 99th percentile wall stress (99th WS), and spatially averaged wall stress (SAWS) for all AAA geometries subject to the choice of a material model combination. Specifically, using a material model combination with a compliant ILT yielded statistically higher wall stresses compared to using a stiff ILT, irrespective of the constitutive equation used to model the AAA wall.</p><p><strong>Discussion: </strong>This work provides quantitative insight into the variability of the wall stress distributions ensuing from AAA FEA modeling due to its strong dependency on population-averaged soft tissue material characterizations. This dependency leads to uncertainty about the true biomechanical state of stress of an individual AAA and the subsequent assessment of its rupture risk.</p>","PeriodicalId":54322,"journal":{"name":"Cardiovascular Engineering and Technology","volume":" ","pages":"66-78"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11892800/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142523665","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":"The Influence of Material Properties and Wall Thickness on Predicted Wall Stress in Ascending Aortic Aneurysms: A Finite Element Study.","authors":"Yu Zhu, Selene Pirola, M Yousuf Salmasi, Sumesh Sasidharan, Serena M Fisichella, Declan P O'Regan, James E Moore, Thanos Athanasiou, Xiao Yun Xu","doi":"10.1007/s13239-024-00756-9","DOIUrl":"10.1007/s13239-024-00756-9","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Purpose: &lt;/strong&gt;Finite element analysis (FEA) has been used to predict wall stress in ascending thoracic aortic aneurysm (ATAA) in order to evaluate risk of dissection or rupture. Patient-specific FEA requires detailed information on ATAA geometry, loading conditions, material properties, and wall thickness. Unfortunately, measuring aortic wall thickness and mechanical properties non-invasively poses a significant challenge, necessitating the use of non-patient-specific data in most FE simulations. This study aimed to assess the impact of employing non-patient-specific material properties and wall thickness on ATAA wall stress predictions.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;FE simulations were performed on 13 ATAA geometries reconstructed from computed tomography angiography (CTA) images. Patient-specific material properties and wall thicknesses were made available from a previous study where uniaxial tensile testing was performed on tissue samples obtained from the same patients. The ATAA wall models were discretised with hexahedral elements and prestressed. For each ATAA model, FE simulations were conducted using patient-specific material properties and wall thicknesses, and group-mean values derived from all tissue samples included in the same experimental study. Literature-based material property and wall thickness were also obtained from the literature and applied to 4 representative cases. Additional FE simulations were performed on these 4 cases by employing group-mean and literature-based wall thicknesses.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;FE simulations using the group-mean material property produced peak wall stresses comparable to those obtained using patient-specific material properties, with a mean deviation of 7.8%. Peak wall stresses differed by 20.8% and 18.7% in patients with exceptionally stiff or compliant walls, respectively. Comparison to results using literature-based material properties revealed larger discrepancies, ranging from 5.4% to 28.0% (mean 20.1%). Bland-Altman analysis showed significant discrepancies in areas of high wall stress, where wall stress obtained using patient-specific and literature-based properties differed by up to 674 kPa, compared to 227 kPa between patient-specific and group-mean properties. Regarding wall thickness, using the literature-based value resulted in even larger discrepancies in predicted peak stress, ranging from 24.2% to 30.0% (mean 27.3%). Again, using the group-mean wall thickness offered better predictions with a difference less than 5% in three out of four cases. While peak wall stresses were most affected by the choice of mechanical properties or wall thickness, the overall distribution of wall stress hardly changed.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;Our study demonstrated the importance of incorporating patient-specific material properties and wall thickness in FEA for risk prediction of aortic dissection or rupture. Our future efforts will focus on developing inverse ","PeriodicalId":54322,"journal":{"name":"Cardiovascular Engineering and Technology","volume":" ","pages":"52-65"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11821800/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142512964","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":"Amplification of Secondary Flow at the Initiation Site of Intracranial Sidewall Aneurysms.","authors":"Benjamin Csippa, Péter Friedrich, István Szikora, György Paál","doi":"10.1007/s13239-025-00771-4","DOIUrl":"https://doi.org/10.1007/s13239-025-00771-4","url":null,"abstract":"<p><strong>Purpose: </strong>The initiation of intracranial aneurysms has long been studied, mainly by the evaluation of the wall shear stress field. However, the debate about the emergence of hemodynamic stimuli still persists. This paper builds on our previous hypothesis that secondary flows play an important role in the formation cascade by examining the relationship between flow physics and vessel geometry.</p><p><strong>Methods: </strong>A composite evaluation framework was developed to analyze the simulated flow field in perpendicular cross-sections along the arterial centerline. The velocity field was decomposed into secondary flow components around the centerline in these cross-sections, allowing the direct comparison of the flow features with the geometrical parameters of the centerline. Qualitative and statistical analysis was performed to identify links between morphology, flow, and the formation site of the aneurysms.</p><p><strong>Results: </strong>The normalized mean curvature and curvature peak were significantly higher in the aneurysmal bends than in other arterial bends. Similarly, a significant difference was found for the normalized mean velocity ( <math><mrow><mi>p</mi> <mo>=</mo> <mn>0.0274</mn></mrow> </math> ), the circumferential ( <math><mrow><mi>p</mi> <mo>=</mo> <mn>0.0029</mn></mrow> </math> ), and radial ( <math><mrow><mi>p</mi> <mo>=</mo> <mn>0.0057</mn></mrow> </math> ) velocity components between the arterial bends harboring the aneurysm than in other arterial bends. In contrast, the difference of means for the normalized axial velocity is insignificant ( <math><mrow><mi>p</mi> <mo>=</mo> <mn>0.1471</mn></mrow> </math> ).</p><p><strong>Conclusion: </strong>Thirty cases with aneurysms located on the ICA were analyzed in the virtually reconstructed pre-aneurysmal state by an in-silico study. We found that sidewall aneurysm formation on the ICA is more probable in these arterial bends with the highest case-specific curvature, which are accompanied by the highest case-specific secondary flows (circumferential and radial velocity components) than in other bends.</p>","PeriodicalId":54322,"journal":{"name":"Cardiovascular Engineering and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143054110","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":"Design and Validation of a High-Fidelity Left Atrial Cardiac Simulator for the Study and Advancement of Left Atrial Appendage Occlusion.","authors":"Keegan Mendez, Manisha Singh, Patrick Willoughby, Beatrice Ncho, Aileen Liao, Susan Su, Megan Lim, Elijah Lee, Mohamad Alkhouli, Hasan Alarouri, Ellen T Roche","doi":"10.1007/s13239-025-00773-2","DOIUrl":"https://doi.org/10.1007/s13239-025-00773-2","url":null,"abstract":"<p><strong>Purpose: </strong>Atrial fibrillation (AF) is the most common chronic cardiac arrhythmia that increases the risk of stroke, primarily due to thrombus formation in the left atrial appendage (LAA). Left atrial appendage occlusion (LAAO) devices offer an alternative to oral anticoagulation for stroke prevention. However, the complex and variable anatomy of the LAA presents significant challenges to device design and deployment. Current benchtop models fail to replicate both anatomical variability and physiological hemodynamics, limiting their utility. This study introduces a novel left atrial cardiac simulator that incorporates patient-derived LAA models within a benchtop circulatory flow loop, enabling high-fidelity LAAO device testing and development.</p><p><strong>Methods: </strong>A rigid, patient-derived left atrium (LA) model was 3D printed from segmented MRI data and modified to accommodate attachment of patient-specific LAA models. A library of LAA geometries was fabricated using silicone casting techniques to replicate the mechanical properties of native tissue. The LA-LAA model was integrated into a circulatory flow loop equipped with a pulsatile pump, pressure sensors, and flow probes, allowing real-time hemodynamic analysis. System tunability was demonstrated by varying heart rate, stroke volume, resistance, and compliance to simulate physiological and pathological conditions.</p><p><strong>Results: </strong>The simulator accurately replicated LA pressure and flow waveforms, closely approximating physiological conditions. Changes in heart rate, stroke volume, and compliance effectively modulated LAP and LA inflow before and after LAAO. Distinct pressure and flow waveforms were observed with different LAA geometries. Hemodynamic analysis revealed increased left atrial pulse pressure after occlusion, with the greatest increase occurring after complete exclusion of the LAA. The simulator facilitated the evaluation of LAAO device performance, including metrics such as seal and PDL, and served as an effective training tool for iterative device deployment and recapture with visual and imaging-guided feedback.</p><p><strong>Conclusions: </strong>The left atrial cardiac simulator offers a highly tunable and realistic platform for testing and developing LAAO devices. It also serves as an effective procedural training tool, allowing for the simulation of patient-specific anatomical and hemodynamic conditions. By enabling these advanced simulations, the simulator enhances pre-procedural planning, device sizing, and placement. This innovation represents a significant step toward advancing personalized medicine in atrial fibrillation management and improving LAAO outcomes.</p>","PeriodicalId":54322,"journal":{"name":"Cardiovascular Engineering and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143054122","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":"Arteriolar Elasticity Measurement in the Fingertip Based on Photoplethysmographic Volume-Oscillometry: A New Approach to the Assessment of Vasomotor Functions in the Microvasculature.","authors":"Ken-Ichi Yamakoshi, Peter Rolfe, Takehiro Yamakoshi","doi":"10.1007/s13239-025-00772-3","DOIUrl":"https://doi.org/10.1007/s13239-025-00772-3","url":null,"abstract":"<p><strong>Purpose: </strong>Dysfunction of vasomotor reactions due to arteriolar smooth muscle causes serious adverse events, such as loss of hemodynamic coherence. This in turn can increase risks of cardiovascular-related diseases. A noninvasive and quantitative evaluation of microvascular disorder is therefore very important for early diagnosis and treatment. This paper describes a new approach to the assessment of vasomotor functions using the arteriolar elasticity measurement technique in the fingertip.</p><p><strong>Methods: </strong>A recently developed device, modified to detect a photoplethysmogram with green light (gPPG) in arteriolar regions, allowed the measurement of arteriolar blood pressure (BP_ca.) and gPPG from a left index fingertip placed on an occlusive cuff of the device. Arteriolar stiffness and distensibility were analyzed as effective elasticity indices, as a function of arteriolar distending pressure derived by volume-oscillometry. Cold pressor tests to induce vasoconstriction were carried out whether appropriate elasticity changes could be obtained.</p><p><strong>Results: </strong>Experiments using 6 healthy subjects were successfully made to obtain arteriolar elastic properties before and while immersing a right hand in cold water. The index-values of stiffness and distensibility showed, respectively, a considerable increase and decrease, clearly demonstrating the appropriate elasticity changes with vasoconstrictive reactions.</p><p><strong>Conclusion: </strong>Although a further study using many subjects is needed, the results so far suggest that this method could easily provide important features to acquire quantitatively arteriolar elasticity together with BP_ca. and to assess vasomotor functions in the microvasculature. This convenient method appears useful for clinical practices and health management and promising also for screening cardiovascular-related diseases. (242/250 words).</p>","PeriodicalId":54322,"journal":{"name":"Cardiovascular Engineering and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143016373","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":"Early-stage Development of the CoRISMA Mechanical Circulatory Support (CMCS) System for Heart Failure Therapy.","authors":"Gretel Monreal, Steven C Koenig, James F Kelley, Jessica J Illg, Daniel Tamez, Mark S Kelley, Varun Yetukuri, Daisy P Cross, Michael E Theran, Mark S Slaughter","doi":"10.1007/s13239-024-00743-0","DOIUrl":"10.1007/s13239-024-00743-0","url":null,"abstract":"<p><strong>Purpose: </strong>CoRISMA MCS Systems Inc (Hamden CT) is developing an innovative mechanical circulatory support system (CMCS) as a durable therapeutic option for heart failure (HF) patients. The CMCS system is comprised of an axial flow pump, non-contacting hydrodynamic bearings, and integrated DC motor designed to be fully implantable in a left atrial (LA) to aortic (Ao) configuration; this unloading strategy may be particularly beneficial for HF patients with preserved ejection fraction (HFpEF). The small (5.5 cm³), lightweight (20 g), and low power (5-7 W) device design should allow for a less invasive off-pump implant. We present early-stage engineering development and testing of the prototype CoRISMA pumps.</p><p><strong>Methods: </strong>Computational fluid dynamics (CFD) modeling was performed to evaluate flow and shear in two impeller (3 blades, 0.5 mm thickness, 8.9 mm diameter, 0.15 mm gap, polished titanium) and diffusor (5 blades, polished titanium) candidate designs. Test apparatuses were custom built to expedite development of the impeller/diffuser designs and iteratively refine the CFD models. Two candidate impeller/diffusor designs were fabricated and tested in each of the two test apparatuses (n = 4 impeller/diffuser + test fixture configurations) in static mock flow loops (hydrodynamic H-Q curves, 3.5 cP glycerol solution at 37 °C), and in dynamic mock flow loops (hemodynamics, 3.5 cP glycerol solution at 37 °C) tuned to HF conditions (mean aortic pressure 50 mmHg, central venous pressure 15 mmHg, aortic flow 3.0 L/min, and heart rate 80 bpm).</p><p><strong>Results: </strong>CFD predicted flows of 4.56 L/min and 4.82 L/min at 100 mmHg for impellers/diffusers 1 and 2, respectively. Impeller 2 required less torque to generate a 6% increase in fluidic flow, and the diffuser had a larger area of high pressure, indicative of lower friction, which likely contributed to the increased efficiency. Experimental testing for all four configurations in the static and dynamic mock loops met performance metrics as evidenced by generating 4.0-4.5 L/min flow against 70-76 mmHg pressure at 25,000 rpm and restoring hemodynamics in the dynamic mock flow loop (MAP = 80 mmHg, CVP = 0 mmHg, total flow = 5.5 L/min) from baseline simulated HF test conditions.</p><p><strong>Conclusion: </strong>These results demonstrate proof-of-concept of the early engineering design and performance of the prototype CoRISMA pumps. Engineering specifications, challenges observed, and proposed solutions for the next design iteration were identified for the continued development of an effective, reliable, and safe LA-to-Ao CMCS system for HF patients. Current design plans are underway for incorporating a wireless energy transfer system for communication and power, eliminating the need for and complications associated with an external driveline, to achieve a fully-implantable system.</p>","PeriodicalId":54322,"journal":{"name":"Cardiovascular Engineering and Technology","volume":" ","pages":"667-678"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141735665","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":"Comments on: \"Preclinical Proof-of-Concept of a Minimally Invasive Direct Cardiac Compression Device for Pediatric Heart Support\".","authors":"T Triwiyanto, I Putu Alit Pawana, Sari Luthfiyah","doi":"10.1007/s13239-024-00751-0","DOIUrl":"10.1007/s13239-024-00751-0","url":null,"abstract":"","PeriodicalId":54322,"journal":{"name":"Cardiovascular Engineering and Technology","volume":" ","pages":"775-776"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142332382","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":"Comparative Study of Single Opening&Closing and Continuous Pulsatile Flow Valve Tester.","authors":"Hao Wang, Zhiqian Lu, Zhongxi Zhou, Li Liu, Zhaoming He","doi":"10.1007/s13239-024-00747-w","DOIUrl":"10.1007/s13239-024-00747-w","url":null,"abstract":"<p><strong>Purpose: </strong>The purpose is to demonstrate the difference in closing volume fraction between the single opening&closing valve tester (SOCVT) and continuous pulsatile flow valve tester (CPFVT).</p><p><strong>Methods: </strong>A comparative study was conducted in four hemodynamic conditions selected from the ISO 5840 on the four mitral valve states: normal annulus, 40% annulus dilation, 60% annulus dilation, and repaired valve with a clip device in both the SOCVT and CPFVT. The closing volume fractions were compared and errors calculated in the 16 cases.</p><p><strong>Results: </strong>In the CPFVT, the flowrate waveform depends more on hemodynamic conditions rather than the valve morphology. For closing volume fractions in the two testers, twelve cases had errors between 10% and 20% and 3 cases had errors between 2.2% and 5.5%. There was no statistic difference in the closing volume fraction between the CPFVT and SOCVT for the normal annulus, 40% valve annulus dilation, 60% valve annulus dilation and repaired valves (P values = 0.44, 0.44, 0.33, and 0.08, respectively, n = 4).</p><p><strong>Conclusion: </strong>There is certain error in closing volume measurements, even if no statistic difference in closing volume measured by the SOCVT and CPFVT. The typical flow waveforms of the mitral valve may be available to standardize testing of the SOCVT to evaluate valve hemodynamics. The SOCVT may be an alternative to the valve testing.</p>","PeriodicalId":54322,"journal":{"name":"Cardiovascular Engineering and Technology","volume":" ","pages":"716-723"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142005837","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}