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Dynamic motion of heart valve

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https://www.readbyqxmd.com/read/27866678/patient-specific-cfd-models-for-intraventricular-flow-analysis-from-3d-ultrasound-imaging-comparison-of-three-clinical-cases
#1
A M Bavo, A M Pouch, J Degroote, J Vierendeels, J H Gorman, R C Gorman, P Segers
BACKGROUND: As the intracardiac flow field is affected by changes in shape and motility of the heart, intraventricular flow features can provide diagnostic indications. Ventricular flow patterns differ depending on the cardiac condition and the exploration of different clinical cases can provide insights into how flow fields alter in different pathologies. METHODS: In this study, we applied a patient-specific computational fluid dynamics model of the left ventricle and mitral valve, with prescribed moving boundaries based on transesophageal ultrasound images for three cardiac pathologies, to verify the abnormal flow patterns in impaired hearts...
November 11, 2016: Journal of Biomechanics
https://www.readbyqxmd.com/read/27815409/a-new-beating-heart-mitral-and-aortic-valve-assessment-model-with-implications-for-valve-intervention-training
#2
Wobbe Bouma, Jayant S Jainandunsing, Arash Khamooshian, Pim van der Harst, Massimo A Mariani, Ehsan Natour
OBJECTIVES: A thorough understanding of mitral and aortic valve motion dynamics is essential in mastering the skills necessary for performing successful valve intervention (open or transcatheter repair or replacement). We describe a reproducible and versatile beating-heart mitral and aortic valve assessment and valve intervention training model in human cadavers. METHODS: The model is constructed by bilateral ligation of the pulmonary veins, ligation of the supra-aortic arteries, creating a shunt between the descending thoracic aorta and the left atrial appendage with a vascular prosthesis, anastomizing a vascular prosthesis to the apex and positioning an intra-aortic balloon pump (IABP) in the vascular prosthesis, cross-clamping the descending thoracic aorta, and finally placing a fluid line in the shunt prosthesis...
November 3, 2016: Interactive Cardiovascular and Thoracic Surgery
https://www.readbyqxmd.com/read/27773869/valve-in-valve-outcome-design-impact-of-a-pre-existing-bioprosthesis-on-the-hydrodynamics-of-an-edwards-sapien-xt-valve
#3
Christian Doose, Maximilian K├╝tting, Sandrine Egron, Pejman Farhadi Ghalati, Christoph Schmitz, Marc Utzenrath, Alexander Sedaghat, Buntaro Fujita, Thomas Schmitz-Rode, Stephan Ensminger, Ulrich Steinseifer
OBJECTIVES: Bioprosthetic aortic heart valves are increasingly implanted in younger patients. Therefore, a strategy for potential valve failure should be developed before implanting the 'first valve'. The goal of this in vitro study was to provide insight into the effects of the design of a bioprosthesis on a valve-in-valve implanted Sapien XT valve. METHODS: The hydrodynamic performance of a 23-mm Sapien XT valve implanted in Vascutek Aspire, Edwards Perimount, Medtronic Mosaic and St...
October 23, 2016: European Journal of Cardio-thoracic Surgery
https://www.readbyqxmd.com/read/27618494/patient-specific-simulation-of-cardiac-blood-flow-from-high-resolution-ct
#4
Jonas Lantz, Lilian Henriksson, Anders Persson, Matts Karlsson, Tino Ebbers
Cardiac hemodynamics can be computed from medical imaging data, and results could potentially aid in cardiac diagnosis and treatment optimization. However, simulations are often based on simplified geometries, ignoring features such as papillary muscles and trabeculae due to their complex shape, limitations in image acquisitions, and challenges in computational modeling. This severely hampers the use of computational fluid dynamics in clinical practice. The overall aim of this study was to develop a novel numerical framework that incorporated these geometrical features...
September 12, 2016: Journal of Biomechanical Engineering
https://www.readbyqxmd.com/read/27164902/on-x-heart-valve-prosthesis-numerical-simulation-of-hemodynamic-performance-in-accelerating-systole
#5
Nima Mirkhani, Mohammad Reza Davoudi, Pedram Hanafizadeh, Daryoosh Javidi, Niloofar Saffarian
Numerical simulation of the bileaflet mechanical heart valves (BMHVs) has been of interest for many researchers due to its capability of predicting hemodynamic performance. A lot of studies have tried to simulate this three-dimensional complex flow in order to analyze the effect of different valve designs on the blood flow pattern. However, simplified models and prescribed motion for the leaflets were utilized. In this paper, transient complex blood flow in the location of ascending aorta has been investigated in a realistic model by fully coupled simulation...
September 2016: Cardiovascular Engineering and Technology
https://www.readbyqxmd.com/read/26968855/a-computational-framework-for-personalized-blood-flow-analysis-in-the-human-left-atrium
#6
Tomohiro Otani, Abdullah Al-Issa, Amir Pourmorteza, Elliot R McVeigh, Shigeo Wada, Hiroshi Ashikaga
Atrial fibrillation (AF), the most common human arrhythmia, is a marker of an increased risk of embolic stroke. However, recent studies suggest that AF may not be mechanistically responsible for the stroke events. An alternative explanation for the mechanism of intracardiac thrombosis and stroke in patients with AF is structural remodeling of the left atrium (LA). Nevertheless, a mechanistic link between LA structural remodeling and intracardiac thrombosis is unclear, because there is no clinically feasible methodology to evaluate the complex relationship between these two phenomena in individual patients...
March 11, 2016: Annals of Biomedical Engineering
https://www.readbyqxmd.com/read/26945836/abnormal-distortion-of-aortic-corevalve-bioprosthesis-with-suicide-left-ventricle-aortic-insufficiency-and-severe-mitral-regurgitation-during-transcatheter-aortic-valve-replacement
#7
Ferdinand Leya, J Michael Tuchek, Walter Coats
We present a patient with critical degenerative aortic stenosis, mitral annular and aortomitral continuity calcification, and senile sigmoid septal hypertrophy who underwent transcatheter aortic valve replacement using the CoreValve bioprosthesis. Immediately after predilation of the aortic valve (18-mm balloon), the patient developed severe hypotension and dynamic left ventricular outflow tract (LVOT) obstruction with systolic anterior motion of the anterior mitral leaflet, causing severe mitral regurgitation...
March 4, 2016: Catheterization and Cardiovascular Interventions
https://www.readbyqxmd.com/read/26919069/investigating-the-impact-of-non-newtonian-blood-models-within-a-heart-pump
#8
Mohammed G Al-Azawy, A Turan, A Revell
A detailed Computational Fluid Dynamics (CFD) study of transient, turbulent blood flow through a positive displacement left ventricular assist device (LVAD) is performed. Two common models for Non-Newtonian blood flow are compared to the Newtonian model to investigate their impact on predicted levels of shear rate and wall shear stress. Given that both parameters are directly relevant to the evaluation of risk from thrombus and haemolysis, there is a need to assess the sensitivity to modelling non-Newtonian flow effects within a pulsatile turbulent flow, in order to identify levels of uncertainly in CFD...
February 26, 2016: International Journal for Numerical Methods in Biomedical Engineering
https://www.readbyqxmd.com/read/26744343/novel-imaging-strategies-for-the-detection-of-prosthetic-heart-valve-obstruction-and-endocarditis
#9
W Tanis, R P J Budde, I A C van der Bilt, B Delemarre, G Hoohenkerk, J-K van Rooden, A M Scholtens, J Habets, S Chamuleau
Prosthetic heart valve (PHV) dysfunction remains difficult to recognise correctly by two-dimensional (2D) transthoracic and transoesophageal echocardiography (TTE/TEE). ECG-triggered multidetector-row computed tomography (MDCT), 18-fluorine-fluorodesoxyglucose positron emission tomography including low-dose CT (FDG-PET) and three-dimensional transoesophageal echocardiography (3D-TEE) may have additional value. This paper reviews the role of these novel imaging tools in the field of PHV obstruction and endocarditis...
February 2016: Netherlands Heart Journal
https://www.readbyqxmd.com/read/26628311/dynamic-left-ventricular-outflow-obstruction-in-situs-inversus-with-levocardia
#10
Kazuhito Hirata, Toshiho Tengan, Hidemitsu Mototake, Minoru Wake
A 69-year-old man with situs inversus, levocardia and inverted great arteries developed severe dynamic left ventricular outflow tract (LVOT) obstruction with systolic anterior motion of the anterior mitral leaflet. There was no asymmetric septal hypertrophy. A possible mechanism of the LOVT obstruction in the present case may have been related to an abnormally long and bent outflow tract resulting from overriding of the right ventricle over the LVOT due to a congenital malposition of the heart. Mitral valve replacement with septal myectomy was performed in order to eliminate systolic anterior motion...
December 1, 2015: BMJ Case Reports
https://www.readbyqxmd.com/read/26623139/dynamic-obstruction-induced-by-systolic-anterior-motion-of-the-mitral-valve-in-a-volume-depleted-left-ventricle-an-unexpected-cause-of-acute-heart-failure-in-a-patient-with-chronic-obstructive-pulmonary-disease
#11
Suji Kim, So Jeong Kim, Jina Kim, Phillhoon Yoon, Jeongwoong Park, Jeonggeun Moon
Systolic anterior motion (SAM) of the mitral valve (MV) and left ventricular outflow tract (LVOT) dynamic obstruction (DO) typically occur in hypertrophic cardiomyopathy; however, they can appear in an apparently normal heart in association with changes in cardiac loading conditions and/or hyperdynamic left ventricular (LV) performance. Meanwhile, chronic obstructive pulmonary disease (COPD) can impair LV filling by elevating pulmonary vascular resistance. The authors report a case of transient acute heart failure caused by LVOT DO resulting from SAM of the MV in a severely volume-depleted LV in a patient with acute COPD exacerbation...
September 2015: Journal of Thoracic Disease
https://www.readbyqxmd.com/read/26254331/vorticity-is-a-marker-of-right-ventricular-diastolic-dysfunction
#12
Brett E Fenster, James Browning, Joyce D Schroeder, Michal Schafer, Chris A Podgorski, Jamie Smyser, Lori J Silveira, J Kern Buckner, Jean R Hertzberg
Right ventricular diastolic dysfunction (RVDD) is an important prognostic indicator in pulmonary arterial hypertension (PAH). RV vortex rings have been observed in healthy subjects, but their significance in RVDD is unknown. Vorticity, the local spinning motion of an element of fluid, may be a sensitive measure of RV vortex dynamics. Using four-dimensional (4D) flow cardiac magnetic resonance imaging (CMR), we investigated the relationship between right heart vorticity with echocardiographic indexes of RVDD...
September 15, 2015: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/25961285/numerical-modeling-of-intraventricular-flow-during-diastole-after-implantation-of-bmhv
#13
Boyang Su, Foad Kabinejadian, Hui Qun Phang, Gideon Praveen Kumar, Fangsen Cui, Sangho Kim, Ru San Tan, Jimmy Kim Fatt Hon, John Carson Allen, Hwa Liang Leo, Liang Zhong
This work presents a numerical simulation of intraventricular flow after the implantation of a bileaflet mechanical heart valve at the mitral position. The left ventricle was simplified conceptually as a truncated prolate spheroid and its motion was prescribed based on that of a healthy subject. The rigid leaflet rotation was driven by the transmitral flow and hence the leaflet dynamics were solved using fluid-structure interaction approach. The simulation results showed that the bileaflet mechanical heart valve at the mitral position behaved similarly to that at the aortic position...
2015: PloS One
https://www.readbyqxmd.com/read/25927407/sudden-hypoxemia-after-uneventful-laparoscopic-cholecystectomy-another-form-of-sam-presentation
#14
Yoshihisa Fujita, Nobuyuki Kagiyama, Yuka Sakuta, Masatsugu Tsuge
BACKGROUND: Perioperative dynamic left ventricular outflow obstruction associated with systolic anterior motion of the mitral valve is well recognized as a cause for unexplained sudden hypotension in perioperative settings, even without underlying heart diseases such as hypertrophic obstructive cardiomyopathy. We treated a patient who experienced sudden hypoxemia without severe hypotension during emergence from anesthesia after an uneventful laparoscopic cholecystectomy. CASE PRESENTATION: A 65-year-old female patient with a history of hypertension presented a sudden decrease in oxygen saturation to 80% after an uneventful cholecystectomy...
April 16, 2015: BMC Anesthesiology
https://www.readbyqxmd.com/read/25924797/dynamic-left-ventricular-outflow-tract-obstruction-secondary-to-hypovolemia-in-a-german-shepard-dog-with-splenic-hemangiosarcoma
#15
Takuma Aoki, Hiroshi Sunahara, Keisuke Sugimoto, Tetsuro Ito, Eiichi Kanai, Sakurako Neo, Yoko Fujii, Yoshito Wakao
Dynamic left ventricular outflow tract obstruction (DLVOTO) is a common condition in cats and humans. In this case report, a dog is described with DLVOTO secondary to severe intra-abdominal hemorrhage caused by a hemangiosarcoma. The dog was a 9-year-old, 35.7-kg, spayed female German Shepard dog that presented with a history of tachypnea and collapse. A Levine II/VI systolic murmur was present at the heart base. Abdominal ultrasonography revealed a splenic mass and a large amount of ascites. Echocardiography showed a reduced left ventricular diameter and an increased aortic velocity caused by systolic anterior motion (SAM) of the mitral valve apparatus...
September 2015: Journal of Veterinary Medical Science
https://www.readbyqxmd.com/read/25816074/assessment-of-turbulence-models-for-pulsatile-flow-inside-a-heart-pump
#16
Mohammed G Al-Azawy, A Turan, A Revell
Computational fluid dynamics (CFD) is applied to study the unsteady flow inside a pulsatile pump left ventricular assist device, in order to assess the sensitivity to a range of commonly used turbulence models. Levels of strain and wall shear stress are directly relevant to the evaluation of risk from haemolysis and thrombosis, and thus understanding the sensitivity to these turbulence models is important in the assessment of uncertainty in CFD predictions. The study focuses on a positive displacement or pulsatile pump, and the CFD model includes valves and moving pusher plate...
March 27, 2015: Computer Methods in Biomechanics and Biomedical Engineering
https://www.readbyqxmd.com/read/25587891/design-of-a-pulsatile-flow-facility-to-evaluate-thrombogenic-potential-of-implantable-cardiac-devices
#17
Sivakkumar Arjunon, Pablo Hidalgo Ardana, Neelakantan Saikrishnan, Shalv Madhani, Brent Foster, Ari Glezer, Ajit P Yoganathan
Due to expensive nature of clinical trials, implantable cardiac devices should first be extensively characterized in vitro. Prosthetic heart valves (PHVs), an important class of these devices, have been shown to be associated with thromboembolic complications. Although various in vitro systems have been designed to quantify blood-cell damage and platelet activation caused by nonphysiological hemodynamic shear stresses in these PHVs, very few systems attempt to characterize both blood damage and fluid dynamics aspects of PHVs in the same test system...
April 2015: Journal of Biomechanical Engineering
https://www.readbyqxmd.com/read/25563285/a-mitral-annulus-tracking-approach-for-navigation-of-off-pump-beating-heart-mitral-valve-repair
#18
Feng P Li, Martin Rajchl, John Moore, Terry M Peters
PURPOSE: To develop and validate a real-time mitral valve annulus (MVA) tracking approach based on biplane transesophageal echocardiogram (TEE) data and magnetic tracking systems (MTS) to be used in minimally invasive off-pump beating heart mitral valve repair (MVR). METHODS: The authors' guidance system consists of three major components: TEE, magnetic tracking system, and an image guidance software platform. TEE provides real-time intraoperative images to show the cardiac motion and intracardiac surgical tools...
January 2015: Medical Physics
https://www.readbyqxmd.com/read/25511373/prevalence-of-rheumatic-heart-disease-in-young-adults-from-new-caledonia
#19
Pierre-Henri Ledos, Joel Kamblock, Pierre Bourgoin, Philippe Eono, Jonathan R Carapetis
BACKGROUND: Rheumatic heart disease (RHD) is an important public health issue, particularly in the Pacific region, but its true burden is unknown. OBJECTIVES: To evaluate the prevalence of rheumatic heart disease (RHD) in young adults from New Caledonia, based on echocardiography, and to evaluate the accuracy of dynamic criteria, focusing on mitral valve (MV) leaflet motion. METHODS: Blind analysis of echocardiography by three cardiologists; diagnosis of RHD required at least one dynamic criterion (exaggerated or restricted MV leaflet motion); subjects with morphological criteria (MV leaflet thickening), but without dynamic criteria, were considered as borderline...
January 2015: Archives of Cardiovascular Diseases
https://www.readbyqxmd.com/read/25384414/a-90-year-old-patient-presenting-with-postoperative-hypotension-and-a-new-murmur-a-case-report
#20
Nicholas L Hartog, Aparna Kamath
INTRODUCTION: Hospitalists are frequently consulted on postoperative patients with hypotension. Postoperative hypotension is common and can be due to variety of causes. Systolic anterior motion of the mitral valve leading to left ventricular outflow tract obstruction is a rare cause of postoperative hypotension and can occur without prior structural heart disease. A high index of suspicion can lead to early recognition of this unique condition. CASE PRESENTATION: A 90-year-old Caucasian woman with no known structural heart abnormality was admitted to the intensive care unit with hypotension after a left hip arthroplasty revision...
November 10, 2014: Journal of Medical Case Reports
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