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https://www.readbyqxmd.com/read/28643214/new-generation-devices-for-transfemoral-transcatheter-aortic-valve-replacement-are-superior-compared-with-last-generation-devices-with-respect-to-varc-2-outcome
#1
Julia Seeger, Birgid Gonska, Wolfgang Rottbauer, Jochen Wöhrle
New generation devices for transcatheter aortic valve replacement have been optimized to improve clinical outcome. We compared procedural, in-hospital, 30 days and 12 months outcome of the new generation repositionable Boston Lotus Valve and the balloon-expandable Edwards Sapien 3 valve with the last generation self-expandable Medtronic CoreValve and the balloon-expandable Edwards Sapien XT. Between 2010 and 2015 consecutive patients treated with the Medtronic CoreValve (N = 100), Edwards Sapien XT (N = 100), Edwards Sapien S3 (N = 100) and Boston Lotus device (N = 100) were enrolled...
June 22, 2017: Cardiovascular Intervention and Therapeutics
https://www.readbyqxmd.com/read/28636475/surgical-aortic-valve-replacement-for-stenosis-of-tavi-device
#2
M Sooknunden, M A Radermecker, J O Defraigne, Vincent Tchana-Sato
We here report the case of a stenosis of the CoreValve(®) system due to reduced mobility of prosthesis cusps for which a surgical replacement of the aortic valve was proposed. The exact mechanism leading to this impaired mobility of the leaflets is yet to be determined. We also underline the fact a transcatheter aortic valve implantation (TAVI) device can be replaced by a surgical replacement without excessive operative risks despite the patient being initially considered as high-risk.
March 1, 2017: Acta Chirurgica Belgica
https://www.readbyqxmd.com/read/28630170/characterization-of-aortic-valve-closure-artifact-during-outflow-tract-mapping-correlation-with-hemodynamics-and-mechanical-valves
#3
Jorge Romero, Olujimi Ajijola, Kalyanam Shivkumar, Roderick Tung
BACKGROUND: Premature ventricular contractions originating in the left ventricle outflow tract represent a significant subgroup of patients referred for catheter ablation. Mechanical artifacts from aortic valve leaflet motion may be observed during mapping, although the incidence and characteristics have not been reported. METHODS AND RESULTS: Twenty-eight consecutive patients with left ventricle outflow tract premature ventricular contraction were included. Electric signals recorded on the ablation catheter not coincident with atrial or ventricular depolarization were analyzed on the recording system...
June 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28623503/investigating-the-suitability-of-carbon-nanotube-reinforced-polymer-in-transcatheter-valve-applications
#4
Monica M Rozeik, David J Wheatley, Terence Gourlay
The current delivery size of transcatheter aortic valves, limited by the thickness of their pericardial leaflets, correlates with a high prevalence of major vascular complications. Polyurethane valves can be developed to a fraction of the thickness of pericardial valves through the addition of carbon nanotubes to reinforce their leaflets. This study investigates the suitability of a novel carbon nanotube reinforced leaflet to reduce the delivery profile of transcatheter aortic valves. Carbon nanotube polyurethane composites were developed with thicknesses of 50 μm and their mechanical properties were determined in relation to various environmental effects...
June 16, 2017: Cardiovascular Engineering and Technology
https://www.readbyqxmd.com/read/28622047/repositionable-and-retrievable-lotus-valve-system-for-the-treatment-of-bicuspid-aortic-stenosis-is-it-time-to-treat-all-valves
#5
Roberto Nerla, Fausto Castriota, Antonio Micari, Estevao de Campos Martins, Alberto Cremonesi
INTRODUCTION: For a long time, a bicuspid valve has been considered a contraindication to transcatheter aortic valve implantation (TAVI) due to worse procedural results. Currently available technologies are changing the scenario, with initial experiences reporting much better results with second-generation devices. AREAS COVERED: This review will analyze the risk and potential pitfalls of TAVI on bicuspid valves and will try ascertain how the use of a new-generation fully repositionable device, the Lotus Valve System (LVS), could improve procedural and clinical results in bicuspid anatomies...
June 16, 2017: Expert Review of Medical Devices
https://www.readbyqxmd.com/read/28620766/phenotype-transformation-of-aortic-valve-interstitial-cells-due-to-applied-shear-stresses-within-a-microfluidic-chip
#6
Xinmei Wang, Joohyung Lee, Mir Ali, Jungkyu Kim, Carla M R Lacerda
Despite valvular heart diseases constituting a significant medical problem, the acquisition of information describing their pathophysiology remains difficult. Due to valvular size, role and location within the body, there is a need for in vitro systems that can recapitulate disease onset and progression. This study combines the development of an in vitro model and its application in the mechanical stimulation of valvular cell transformation. Specifically, porcine aortic valvular interstitial cells (PAVIC) were cultured on polydimethylsiloxane microfluidic devices with or without exposure to shear stresses...
June 15, 2017: Annals of Biomedical Engineering
https://www.readbyqxmd.com/read/28616349/sparing-aortic-valve-techniques
#7
Rubén Álvarez-Cabo
Prosthetic valve implantation is the most widely used therapeutic option for aortic regurgitation (AR), but complications associated with prosthetic valves, with an incidence of 3-5% patient/year, and the need for anticoagulation in mechanical valves, force us to consider aortic valve repair as an alternative to the prosthetic implant, especially in young people with many potential years of life for these complications. Aortic valve repair techniques are not excessively complicated, but there is no standardization, so they are not reproducible in all medical centers...
May 2017: Journal of Thoracic Disease
https://www.readbyqxmd.com/read/28616299/rupture-of-right-sinus-of-valsalva-aneurysm-protruding-into-the-pulmonary-artery-with-aortic-and-pulmonary-valve-endocarditis
#8
Tae-Eun Jung, Jong-Hyun Baek, Dong-Hyup Lee
Rupture of right sinus of Valsalva aneurysm (SVA) protruding into the pulmonary artery with aortic and pulmonary valve endocarditis is rare. A 42-year-old man was admitted with fever and dyspnea. He was diagnosed with right sinus of Valsalva rupture with ventricular septal defect (VSD) and vegetation on both aortic and pulmonary valves. Dual exposure technique was performed. The base of the aneurysm sac was closed off, and, together with the VSD, was covered by a Gore-Tex patch. Aortic and pulmonary valves were replaced with mechanical valves...
May 2017: Journal of Thoracic Disease
https://www.readbyqxmd.com/read/28610762/early-trifecta-valve-failure-report-of-a-cluster-of-cases-from-a-tertiary-care-referral-center
#9
Ankur Kalra, Hasan Rehman, Mahesh Ramchandani, Colin M Barker, Gerald M Lawrie, Ross M Reul, Michael J Reardon, Neal S Kleiman
BACKGROUND: The Trifecta valve (St Jude Medical, Inc, St Paul, Minn) was approved for commercial use by the US Food and Drug Administration in 2011. Several isolated cases have been reported since then, describing early structural valve deterioration. We report a case series of 8 Trifecta valve failures, describing patients' clinical substrate and management, and the pathologic characteristics of the explanted valves. METHODS: Trifecta valve failure occurred in 7 patients (8 valves) receiving 19-mm (n = 2), 21-mm (n = 3), 23-mm (n = 1), and 25-mm (n = 2) valves...
May 22, 2017: Journal of Thoracic and Cardiovascular Surgery
https://www.readbyqxmd.com/read/28601321/lysophosphatidylcholine-activates-the-akt-pathway-to-upregulate-extracellular-matrix-protein-production-in-human-aortic-valve-cells
#10
Hui Cheng, Qingzhou Yao, Rui Song, Yufeng Zhai, Wei Wang, David A Fullerton, Xianzhong Meng
BACKGROUND: Overproduction of extracellular matrix (ECM) protein by aortic valve interstitial cells (AVICs) plays an important role in valvular sclerosis (thickening) associated with the early pathobiology of aortic stenosis. Accumulation of oxidized low-density lipoprotein (oxLDL) is observed in sclerotic aortic valve and may have a mechanistic role in valvular disease progression. Lysophosphatidylcholine (LysoPC) is a component of oxLDL and has multiple biological activities. This study was to test the hypothesis that oxLDL and LysoPC upregulate ECM protein production in human AVICs...
June 1, 2017: Journal of Surgical Research
https://www.readbyqxmd.com/read/28599826/prognostic-value-of-left-ventricular-deformation-parameters-in-patients-with-severe-aortic-stenosis-a-pilot-study-of-the-usefulness-of-strain-echocardiography
#11
Lars Gunnar Klaeboe, Trine F Haland, Ida S Leren, Rachel M A Ter Bekke, Pål H Brekke, Helge Røsjø, Torbjørn Omland, Lars Gullestad, Svend Aakhus, Kristina H Haugaa, Thor Edvardsen
BACKGROUND: In patients with aortic stenosis, subtle alterations in myocardial mechanics can be detected by speckle-tracking echocardiography before reduction of left ventricular ejection fraction (LVEF). METHODS: In this prospective study, 162 patients with aortic stenosis with an average aortic valve area of 0.7 ± 0.2 cm(2) and a mean LVEF of 60 ± 11% were included. Global longitudinal strain (GLS) and mechanical dispersion (SD of time from Q/R on the electrocardiogram to peak strain in 16 left ventricular segments) were assessed using echocardiography, and all-cause mortality (n = 37) was recorded during 37 ± 13 months of follow-up...
June 6, 2017: Journal of the American Society of Echocardiography
https://www.readbyqxmd.com/read/28597231/development-of-an-in-vitro-piv-setup-for-preliminary-investigation-of-the-effects-of-aortic-compliance-on-flow-patterns-and-hemodynamics
#12
Martin Büsen, Christian Arenz, Michael Neidlin, Sam Liao, Thomas Schmitz-Rode, Ulrich Steinseifer, Simon J Sonntag
The aorta with its compliance plays a major role in hemodynamics as it saves a portion of ejected blood during systole which is then released in diastole. The aortic compliance decreases with increasing age, which is related to several cardiovascular imparities and diseases. Changes in flow patterns and pressure curves, due to varying aortic compliance, are difficult to investigate in vivo. As a result, the aim of the present work was to develop an in vitro setup enabling standardized investigations on the effect of compliance changes on flow patterns and pressure curves...
June 8, 2017: Cardiovascular Engineering and Technology
https://www.readbyqxmd.com/read/28589644/endothelial-to-mesenchymal-transformation-is-induced-by-altered-extracellular-matrix-in-aortic-valve-endothelial-cells
#13
Sudip Dahal, Peter Huang, Bruce T Murray, Gretchen J Mahler
Alterations in shear stress, mechanical deformation, extracellular matrix (ECM) composition and exposure to inflammatory conditions are known to cause endothelial to mesenchymal transformation (EndMT). This change in endothelial phenotype has only recently been linked to adult pathologies such as cancer progression, organ fibrosis, and calcific aortic valve disease; and its function in adult physiology, especially in response to tissue mechanics, has not been rigorously investigated. EndMT is a response to mechanical and biochemical signals that results in the remodeling of underlying tissues...
June 7, 2017: Journal of Biomedical Materials Research. Part A
https://www.readbyqxmd.com/read/28582640/the-causes-of-thrombocytopenia-after-transcatheter-aortic-valve-implantation
#14
Maciej Mitrosz, Remigiusz Kazimierczyk, Bozena Sobkowicz, Ewa Waszkiewicz, Pawel Kralisz, Marek Frank, Jaroslaw Piszcz, Marzenna Galar, Slawomir Dobrzycki, Wlodzimierz J Musial, Tomasz Hirnle, Karol A Kaminski, Agnieszka M Tycinska
INTRODUCTION: Even though thrombocytopenia following transcatheter aortic valve implantation (TAVI) has been described, further investigation of this phenomenon is needed. AIMS: To determine which factors may explain the fall in platelet count that occurs after implantation of a TAVI device, including markers of platelet and blood coagulation activation. MATERIAL AND METHODS: 32 patients without previous indications for dual antiplatelet therapy (mean age 78...
May 26, 2017: Thrombosis Research
https://www.readbyqxmd.com/read/28579288/movat-pentachrom-stain-reveals-unexpected-high-osteogenesis-rate-in-aortic-valves
#15
Claudia Dittfeld, Michael Haase, Maria Feilmeier, Anett Jannasch, Petra Büttner, Katrin Plötze, Thomas Waldow, Sems-Malte Tugtekin
BACKGROUND AND AIM OF THE STUDY: Aortic valve (AV) stenosis is the most common valvular heart disease with an incidence of 3% for people ≥ 65years in the industrialized world with indication for a surgical or transcatheter valve replacement. Researchers suppose osteogenic processes as key mechanisms in calcific aortic valve stenosis. Recently, Torre et al. published impressive histological analyses and detected osseous and/or chondromatous metaplasia in 15.6% of 6685 native calcified aortic valves...
June 1, 2017: Acta Histochemica
https://www.readbyqxmd.com/read/28576718/effect-of-altered-haemodynamics-on-the-developing-mitral-valve-in-chick-embryonic-heart
#16
Kar Lai Pang, Matthew Parnall, Siobhan Loughna
Intracardiac haemodynamics is crucial for normal cardiogenesis, with recent evidence showing valvulogenesis is haemodynamically dependent and inextricably linked with shear stress. Although valve anomalies have been associated with genetic mutations, often the cause is unknown. However, altered haemodynamics have been suggested as a pathogenic contributor to bicuspid aortic valve disease. Conversely, how abnormal haemodynamics impacts mitral valve development is still poorly understood. In order to analyse altered blood flow, the outflow tract of the chick heart was constricted using a ligature to increase cardiac pressure overload...
May 30, 2017: Journal of Molecular and Cellular Cardiology
https://www.readbyqxmd.com/read/28571486/repositionable-self-expanding-aortic-bioprosthesis
#17
Bruna Gomes, Hugo A Katus, Raffi Bekeredjian
Transcatheter aortic valve implantation/replacement (TAVI or TAVR) has been established as a first line therapy in patients with symptomatic severe aortic stenosis (AS) at high or prohibitive surgical risk and as an alternative in elderly patients with intermediate surgical risk. Since its first-in-human procedure in 2002, the past 15-years have shown rapid developments in TAVI technology with the introduction and further improvement of new transcatheter heart valves (THV). Areas covered: There are currently several THV systems available, based on balloon-expandable, self-expandable or other technologies...
June 14, 2017: Expert Review of Medical Devices
https://www.readbyqxmd.com/read/28571029/roles-of-high-mobility-group-box-1-in-cardiovascular-calcification
#18
Qiang Chen, Ze-Yang Wang, Li-Yuan Chen, Hou-Yuan Hu
Calcific disease of the cardiovascular system, including atherosclerotic calcification, medial calcification in diabetes and calcific aortic valve disease, is an important risk factor for many adverse cardiovascular events such as ischemic cardiac events and subsequent mortality. Although cardiovascular calcification has long been considered to be a passive degenerative occurrence, it is now recognized as an active and highly regulated process that involves osteochondrogenic differentiation, apoptosis and extracellular vesicle release...
June 5, 2017: Cellular Physiology and Biochemistry
https://www.readbyqxmd.com/read/28566471/emergency-treatment-of-decompensated-aortic-stenosis
#19
Dario Bongiovanni, Constantin Kühl, Sabine Bleiziffer, Lynne Stecher, Felix Poch, Martin Greif, Julinda Mehilli, Steffen Massberg, Norbert Frey, Rüdiger Lange, Karl-Ludwig Laugwitz, Gerhard Schymik, Derk Frank, Christian Kupatt
OBJECTIVE: The optimal treatment of patients with acute and severe decompensation of aortic stenosis is unclear due to recent advances in transcatheter interventions and supportive therapies. Our aim was to assess the early outcome of emergency transcatheter aortic valve implantation (eTAVI) versus emergency balloon aortic valvuloplasty (eBAV) followed by TAVI under elective circumstances. METHODS: Emergency conditions were defined as: cardiogenic shock with requirement of catecholamine therapy, severe acute dyspnoea (NYHA IV), cardiac resuscitation or mechanic respiratory support...
May 31, 2017: Heart: Official Journal of the British Cardiac Society
https://www.readbyqxmd.com/read/28559420/incremental-prognostic-use-of-left-ventricular-global-longitudinal-strain-in-asymptomatic-minimally-symptomatic-patients-with-severe-bioprosthetic-aortic-stenosis-undergoing-redo-aortic-valve-replacement
#20
Peyman Naji, Shailee Shah, Lars G Svensson, A Marc Gillinov, Douglas R Johnston, L Leonardo Rodriguez, Richard A Grimm, Brian P Griffin, Milind Y Desai
BACKGROUND: With improved survival of patients undergoing primary bioprosthetic aortic valve replacement (AVR), reoperation to relieve severe prosthetic aortic stenosis (PAS) is increasing. Timing of redo surgery in asymptomatic/minimally symptomatic patients remains controversial. Left ventricular (LV) global longitudinal strain (GLS) is a marker of subclinical LV dysfunction. In asymptomatic/minimally symptomatic patients with severe PAS undergoing redo AVR, we sought to determine whether LV-GLS provides incremental prognostic use...
June 2017: Circulation. Cardiovascular Imaging
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