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Cardiovascular Engineering and Technology

Timothy Ruesink, Rafael Medero, David Rutkowski, Alejandro Roldán-Alzate
PURPOSE: Arterial stiffness has predictive value for cardiovascular disease (CVD). Local artery stiffness can provide insight on CVD pathology and may be useful for diagnosis and prognosis. However, current methods are invasive, require real-time expertise for measurement, or are limited by arterial region. 4D Flow MRI can non-invasively measure local stiffness by estimating local pulse wave velocity (PWV). This technique can be applied to vascular regions, previously accessible only by invasive stiffness measurement methods...
September 14, 2018: Cardiovascular Engineering and Technology
Kristian Valen-Sendstad, Aslak W Bergersen, Yuji Shimogonya, Leonid Goubergrits, Jan Bruening, Jordi Pallares, Salvatore Cito, Senol Piskin, Kerem Pekkan, Arjan J Geers, Ignacio Larrabide, Saikiran Rapaka, Viorel Mihalef, Wenyu Fu, Aike Qiao, Kartik Jain, Sabine Roller, Kent-Andre Mardal, Ramji Kamakoti, Thomas Spirka, Neil Ashton, Alistair Revell, Nicolas Aristokleous, J Graeme Houston, Masanori Tsuji, Fujimaro Ishida, Prahlad G Menon, Leonard D Browne, Stephen Broderick, Masaaki Shojima, Satoshi Koizumi, Michael Barbour, Alberto Aliseda, Hernán G Morales, Thierry Lefèvre, Simona Hodis, Yahia M Al-Smadi, Justin S Tran, Alison L Marsden, Sreeja Vaippummadhom, G Albert Einstein, Alistair G Brown, Kristian Debus, Kuniyasu Niizuma, Sherif Rashad, Shin-Ichiro Sugiyama, M Owais Khan, Adam R Updegrove, Shawn C Shadden, Bart M W Cornelissen, Charles B L M Majoie, Philipp Berg, Sylvia Saalfield, Kenichi Kono, David A Steinman
PURPOSE: Image-based computational fluid dynamics (CFD) is widely used to predict intracranial aneurysm wall shear stress (WSS), particularly with the goal of improving rupture risk assessment. Nevertheless, concern has been expressed over the variability of predicted WSS and inconsistent associations with rupture. Previous challenges, and studies from individual groups, have focused on individual aspects of the image-based CFD pipeline. The aim of this Challenge was to quantify the total variability of the whole pipeline...
September 10, 2018: Cardiovascular Engineering and Technology
Philipp Berg, Samuel Voß, Sylvia Saalfeld, Gábor Janiga, Aslak W Bergersen, Kristian Valen-Sendstad, Jan Bruening, Leonid Goubergrits, Andreas Spuler, Nicole M Cancelliere, David A Steinman, Vitor M Pereira, Tin Lok Chiu, Anderson Chun On Tsang, Bong Jae Chung, Juan R Cebral, Salvatore Cito, Jordi Pallarès, Gabriele Copelli, Benjamin Csippa, György Paál, Soichiro Fujimura, Hiroyuki Takao, Simona Hodis, Georg Hille, Christof Karmonik, Saba Elias, Kerstin Kellermann, Muhammad Owais Khan, Alison L Marsden, Hernán G Morales, Senol Piskin, Ender A Finol, Mariya Pravdivtseva, Hamidreza Rajabzadeh-Oghaz, Nikhil Paliwal, Hui Meng, Santhosh Seshadhri, Matthew Howard, Masaaki Shojima, Shin-Ichiro Sugiyama, Kuniyasu Niizuma, Sergey Sindeev, Sergey Frolov, Thomas Wagner, Alexander Brawanski, Yi Qian, Yu-An Wu, Kent D Carlson, Dan Dragomir-Daescu, Oliver Beuing
PURPOSE: Advanced morphology analysis and image-based hemodynamic simulations are increasingly used to assess the rupture risk of intracranial aneurysms (IAs). However, the accuracy of those results strongly depends on the quality of the vessel wall segmentation. METHODS: To evaluate state-of-the-art segmentation approaches, the Multiple Aneurysms AnaTomy CHallenge (MATCH) was announced. Participants carried out segmentation in three anonymized 3D DSA datasets (left and right anterior, posterior circulation) of a patient harboring five IAs...
September 6, 2018: Cardiovascular Engineering and Technology
Scott A Metzler, Steven C Waller, James N Warnock
Current protocols for mechanical preconditioning of tissue engineered heart valves have focused on application of pressure, flexure and fluid flow to stimulate collagen production, ECM remodeling and improving mechanical performance. The aim of this study was to determine if mechanical preconditioning with cyclic stretch could promote an intact endothelium that resembled the viability and morphology of a native valve. Confocal laser scanning microscopy was used to image endothelial cells on aortic valve strips subjected to static incubation or physiological strain regimens...
August 23, 2018: Cardiovascular Engineering and Technology
Anna Nikishova, Lourens Veen, Pavel Zun, Alfons G Hoekstra
Coronary artery stenosis, or abnormal narrowing, is a widespread and potentially fatal cardiac disease. After treatment by balloon angioplasty and stenting, restenosis may occur inside the stent due to excessive neointima formation. Simulations of in-stent restenosis can provide new insight into this process. However, uncertainties due to variability in patient-specific parameters must be taken into account. We performed an uncertainty quantification (UQ) study on a complex two-dimensional in-stent restenosis model...
August 22, 2018: Cardiovascular Engineering and Technology
Giulia Luraghi, Francesco Migliavacca, Josè Fèlix Rodriguez Matas
The performance of heart valves, either native or artificial, can be evaluated by means of finite element analyses, either from a structural or a fluid-structure interaction (FSI) point of view. The latter captures the coupling between the valve leaflets and the blood in a more realistic way. The selection of the appropriate finite elements approach for the model is the first and fundamental step to achieve accurate simulations. The aim of this work is to investigate the influence of the type, formulation, size, and shape of the elements in heart valves simulations...
August 21, 2018: Cardiovascular Engineering and Technology
Alireza Rezvani-Sharif, Mohammad Tafazzoli-Shadpour, Alberto Avolio
Atherosclerosis is a major risk factor for cardiovascular disease. However, mechanisms of interaction of atherosclerotic plaque development and local stiffness of the lamellar structure of the arterial wall are not well established. In the current study, the local Young's modulus of the wall and plaque components were determined for three different groups of healthy, mildly diseased and advanced atherosclerotic human abdominal aortas. Histological staining was performed to highlight the atherosclerotic plaque components and lamellar structure of the aortic media, consisting of concentric layers of elastin and interlamellar zones...
July 13, 2018: Cardiovascular Engineering and Technology
(no author information available yet)
No abstract text is available yet for this article.
September 2018: Cardiovascular Engineering and Technology
Ramji Iyer, Aaron Chalekian, Randy Lane, Mike Evans, Seung Yi, John Morris
Transcatheter Mitral Valve Replacement (TMVR) is currently under clinical investigation as a viable treatment option for mitral regurgitation (MR). Therefore, it is important to outline the key functional requirements of a TMVR prosthesis in order to provide an overall approach to assessing mitral valve replacement devices utilizing a combination of in vitro and preclinical methods. This article provides a review of the mitral valve disease as well as general considerations and guidance for developing a TMVR device based on International Industry Standards...
September 2018: Cardiovascular Engineering and Technology
Deepa Sritharan, Parinaz Fathi, Jason D Weaver, Stephen M Retta, Changfu Wu, Nandini Duraiswamy
After implantation of a transcatheter bioprosthetic heart valve its original circular circumference may become distorted, which can lead to changes in leaflet coaptation and leaflets that are stretched or sagging. This may lead to early structural deterioration of the valve as seen in some explanted transcatheter heart valves. Our in vitro study evaluates the effect of leaflet deformations seen in elliptical configurations on the damage patterns of the leaflets, with circular valve deformation as the control...
September 2018: Cardiovascular Engineering and Technology
Pezhman Hafez, Shiplu R Chowdhury, Shinsmon Jose, Jia Xian Law, B H I Ruszymah, Abdul Rahman Mohd Ramzisham, Min Hwei Ng
Developing experimental models to study ischemic heart disease is necessary for understanding of biological mechanisms to improve the therapeutic approaches for restoring cardiomyocytes function following injury. The aim of this study was to develop an in vitro hypoxic/re-oxygenation model of ischemia using primary human cardiomyocytes (HCM) and define subsequent cytotoxic effects. HCM were cultured in serum and glucose free medium in hypoxic condition with 1% O2 ranging from 30 min to 12 h. The optimal hypoxic exposure time was determined using Hypoxia Inducible Factor 1α (HIF-1α) as the hypoxic marker...
September 2018: Cardiovascular Engineering and Technology
Yueh-Hsun Lu, Karthick Mani, Bivas Panigrahi, Saurabh Hajari, Chia-Yuan Chen
In the current scenario of endovascular intervention, surgeons have to manually navigate the catheter within the complex vasculature of the human body under the guidance of X-ray. This manual intervention upsurges the possibilities of vessel damage due to frequent contact between the catheter and vasculature wall. In this context, a shape memory alloy-based miniaturized actuator was proposed in this study with a specific aim to reduce vessel wall related damage by improving the bending motions of the guidewire tip in a semi-automatic fashion...
September 2018: Cardiovascular Engineering and Technology
Manuel K Rausch, Marcin Malinowski, William D Meador, Penny Wilton, Asghar Khaghani, Tomasz A Timek
The tricuspid annulus shows significant alterations in patients with functional tricuspid regurgitation-tricuspid valve dysfunction that is secondary to other diseases such as pulmonary hypertension. Early changes in annular shape and dynamics may provide an understanding of disease mechanisms and could predict disease progression. To gain a mechanistic insight into these early changes we perform a spatially-resolved analysis of the effect of acute pulmonary hypertension on the tricuspid annulus in sheep. To this end, we suture sonomicrometry crystals to the annulus of nine sheep and record their locations in the beating heart, before and after inducing acute pulmonary hypertension...
September 2018: Cardiovascular Engineering and Technology
Jevgenia Zilberman-Rudenko, Frank Z Zhao, Stephanie E Reitsma, Annachiara Mitrugno, Jiaqing Pang, Joseph J Shatzel, Beth Rick, Christina Tyrrell, Wohaib Hasan, Owen J T McCarty, Martin A Schreiber
Platelet apheresis units are transfused into patients to mitigate or prevent bleeding. In a hospital, platelet apheresis units are transported from the transfusion service to the healthcare teams via two methods: a pneumatic tubing system (PTS) or ambulatory transport. Whether PTS transport affects the activity and utility of platelet apheresis units is unclear. We quantified the gravitational forces and transport time associated with PTS and ambulatory transport within our hospital. Washed platelets and supernatants were prepared from platelet apheresis units prior to transport as well as following ambulatory or PTS transport...
September 2018: Cardiovascular Engineering and Technology
Claudio Chiastra, Maik J Grundeken, Carlos Collet, Wei Wu, Joanna J Wykrzykowska, Giancarlo Pennati, Gabriele Dubini, Francesco Migliavacca
The treatment of coronary bifurcations is challenging for interventional cardiologists. The Tryton stent (Tryton Medical, Inc., USA) is one of the few devices specifically designed for coronary bifurcations that underwent large clinical trials. Although the manufacturer provides specific recommendations to position the stent in the bifurcation side branch (SB) according to four radio-opaque markers under angiographic guidance, wrong device positioning may accidentally occur. In this study, the virtual bench testing approach was used to investigate the impact of wrong positioning of the Tryton stent in coronary bifurcations in terms of geometrical and biomechanical criteria...
September 2018: Cardiovascular Engineering and Technology
Francesco Scardulla, Valentina Agnese, Giuseppe Romano, Gabriele Di Gesaro, Sergio Sciacca, Diego Bellavia, Francesco Clemenza, Michele Pilato, Salvatore Pasta
The risk of right ventricle (RV) failure remains a major contraindication for continuous-flow left ventricular assist device (CF-LVAD) implantation in patients with heart failure. It is therefore critical to identify the patients who will benefit from early intervention to avoid adverse outcomes. We sought to advance the computational modeling description of the mechanisms underlying RV failure in LVAD-supported patients. RV failure was studied by computational modeling of hemodynamic and cardiac mechanics using lumped-parameter and biventricular finite element (FE) analysis...
September 2018: Cardiovascular Engineering and Technology
Ranjeeta Subramaniam, Mohan Prasath Mani, Saravana Kumar Jaganathan
In this study, a small vascular graft based on polyurethane (PU) blended with chitosan (Ch) nanoparticles was fabricated using electrospinning technique. Initially, the chitosan nanoparticles were synthesized using ionic gelation method. UV-Vis spectrophotometer confirmed the presence of synthesized Ch nanoparticles by exhibiting absorption peak at 288 nm and the Fourier-transform infrared spectroscopy (FTIR) analysis confirmed the existence of the chitosan. Further, the synthesized Ch nanoparticles showed size diameter in the range of 134 ± 58 nm as measured using ImageJ...
September 2018: Cardiovascular Engineering and Technology
Zhenglun Alan Wei, Simon Johannes Sonntag, Milan Toma, Shelly Singh-Gryzbon, Wei Sun
The governing international standard for the development of prosthetic heart valves is International Organization for Standardization (ISO) 5840. This standard requires the assessment of the thrombus potential of transcatheter heart valve substitutes using an integrated thrombus evaluation. Besides experimental flow field assessment and ex vivo flow testing, computational fluid dynamics is a critical component of this integrated approach. This position paper is intended to provide and discuss best practices for the setup of a computational model, numerical solving, post-processing, data evaluation and reporting, as it relates to transcatheter heart valve substitutes...
September 2018: Cardiovascular Engineering and Technology
Oren M Rotman, Brandon Kovarovic, Chander Sadasivan, Luis Gruberg, Baruch B Lieber, Danny Bluestein
Transcatheter aortic valve replacement (TAVR) is an over-the-wire procedure for treatment of severe aortic stenosis (AS). TAVR valves are conventionally tested using simplified left heart simulators (LHS). While those provide baseline performance reliably, their aortic root geometries are far from the anatomical in situ configuration, often overestimating the valves' performance. We report on a novel benchtop patient-specific arterial replicator designed for testing TAVR and training interventional cardiologists in the procedure...
September 2018: Cardiovascular Engineering and Technology
Oliver I Brown, Andrew L Clark, Raj Chelliah, Benjamin J Davison, Adam N Mather, Michael S Cunnington, Joseph John, Albert Alahmar, Richard Oliver, Konstantinos Aznaouridis, Angela Hoye
Cardiogoniometry (CGM) is method of 3-dimensional electrocardiographic assessment which has been shown to identify patients with angiographically defined, stable coronary artery disease (CAD). However, angiographic evidence of CAD, does not always correlate to physiologically significant disease. The aim of our study was to assess the ability of CGM to detect physiologically significant coronary stenosis defined by fractional flow reserve (FFR). In a tertiary cardiology centre, elective patients with single vessel CAD were enrolled into a prospective double blinded observational study...
September 2018: Cardiovascular Engineering and Technology
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