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https://www.readbyqxmd.com/read/28644382/metal-ion-loaded-nanofibre-matrices-for-calcification-inhibition-in-polyurethane-implants
#1
Charanpreet Singh, Xungai Wang
Pathologic calcification leads to structural deterioration of implant materials via stiffening, stress cracking, and other structural disintegration mechanisms, and the effect can be critical for implants intended for long-term or permanent implantation. This study demonstrates the potential of using specific metal ions (MI)s for inhibiting pathological calcification in polyurethane (PU) implants. The hypothesis of using MIs as anti-calcification agents was based on the natural calcium-antagonist role of Mg(2+) ions in human body, and the anti-calcification effect of Fe(3+) ions in bio-prosthetic heart valves has previously been confirmed...
June 23, 2017: Journal of Functional Biomaterials
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
#2
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/28641192/obstructive-neonatal-atrial-myxoma
#3
Federica Iezzi, Andrea Quarti, Alessandro Capestro, Marco Pozzi
INTRODUCTION: Cardiac myxoma is a benign neoplasm representing the most common primary cardiac tumor in adults, however it is unusual in neonates. It is represented by an endocardial mass that occupies the cardiac chamber. Although the majority of myxomas are attached to the fossa ovalis of the interatrial septum, they also attach to the walls of the cardiac chambers and to valve leaflets surfaces. Approximately 75% of myxomas are found in the left atrium, 20% are located in the right atrium, and rarely in the ventricles...
June 8, 2017: International Journal of Surgery Case Reports
https://www.readbyqxmd.com/read/28639972/imaging-in-repaired-tetralogy-of-fallot-with-a-focus-on-recent-advances-in-echocardiography
#4
Guillermo Larios, Mark K Friedberg
PURPOSE OF REVIEW: Imaging is essential for the management of adults with repaired tetralogy of Fallot (rToF). Echocardiography and cardiac magnetic resonance imaging are the central modalities to assess rToF. Here we review recent literature on imaging rToF, focusing on echocardiography and advances in assessment of cardiac mechanics. RECENT FINDINGS: Several two-dimensional, three-dimensional, and Doppler echo parameters have been proposed to assess pulmonary regurgitation, right ventricular volumes and ejection fraction, but most of them still have important limitations in their feasibility and reliability compared to cardiac magnetic resonance (CMR)...
July 20, 2017: Current Opinion in Cardiology
https://www.readbyqxmd.com/read/28636475/surgical-aortic-valve-replacement-for-stenosis-of-tavi-device
#5
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/28634703/isoperistaltic-versus-antiperistaltic-side-to-side-anastomosis-after-right-laparoscopic-hemicolectomy-for-cancer-isovanti-trial-study-protocol-for-a-randomised-clinical-trial
#6
N Ibañez, J Abrisqueta, J Luján, Q Hernández, P Parrilla
BACKGROUND: It is believed that loosing ileocecal valve is well tolerated in patients who do not have short bowel syndrome or Crohn disease. From the hypothesis of colonic peristalsis and transit is regulated by that ileocecal valvular mechanism, we try to find out if the creation of a new pseudo-valvular mechanism as antiperistaltic anastomosis could be considered after right hemicolectomy can cause any short- or long-term changes in gastrointestinal habits. PURPOSE: The purpose of the study at primary endpoint is to compare early (occurring within 30 days of surgery) and late (occurring during the follow-up) postoperative complications between both groups The purpose of the study at secondary endpoint is to compare intraoperative and postoperative events between experimental and control groups in terms of operating time, first oral tolerance day, first flatus and faeces, length of hospital stay and orocecal transit; comparing rates of gastrointestinal life quality and comparing mortality rates between both groups...
June 21, 2017: International Journal of Colorectal Disease
https://www.readbyqxmd.com/read/28631207/qrs-width-as-a-predictor-of-right-ventricular-remodeling-after-percutaneous-pulmonary-valve-implantation
#7
C Paech, I Dähnert, F T Riede, R Wagner, T Kister, K Nieschke, F Wagner, R A Gebauer
Recent data showed a right ventricular dyssynchrony in patients with tetralogy of Fallot (TOF). Percutaneous pulmonary valve implantation (PPVI) has become an important procedure to treat a pulmonary stenosis and/or regurgitation of the right ventricular outflow tract in these patients. Despite providing good results, there is still a considerable number of nonresponders to PPVI. The authors speculated that electrical dysfunction of the right ventricle plays an underestimated role in the outcome of patients after PPVI...
June 19, 2017: Pediatric Cardiology
https://www.readbyqxmd.com/read/28631145/biaxial-mechanical-properties-of-bovine-jugular-venous-valve-leaflet-tissues
#8
Hsiao-Ying Shadow Huang, Jiaqi Lu
Venous valve incompetence has been implicated in diseases ranging from chronic venous insufficiency (CVI) to intracranial venous hypertension. However, while the mechanical properties of venous valve leaflet tissues are central to CVI biomechanics and mechanobiology, neither stress-strain curves nor tangent moduli have been reported. Here, equibiaxial tensile mechanical tests were conducted to assess the tangent modulus, strength and anisotropy of venous valve leaflet tissues from bovine jugular veins. Valvular tissues were stretched to 60% strain in both the circumferential and radial directions, and leaflet tissue stress-strain curves were generated for proximal and distal valves (i...
June 19, 2017: Biomechanics and Modeling in Mechanobiology
https://www.readbyqxmd.com/read/28630186/loss-of-c-5-sterol-desaturase-activity-results-in-increased-resistance-to-azole-and-echinocandin-antifungals-in-a-clinical-isolate-of-candida-parapsilosis
#9
Jeffrey M Rybak, C Michael Dickens, Josie E Parker, Kelly Caudle, Kayihura Manigaba, Sarah G Whaley, Andrew Nishimoto, Arturo Luna-Tapia, Sujoy Roy, Qing Zhang, Katherine S Barker, Glen E Palmer, Thomas R Sutter, Ramin Homayouni, Nathan P Wiederhold, Steven L Kelly, P David Rogers
Among emerging non-albicans Candida species, C. parapsilosis is of particular concern as a cause of nosocomial bloodstream infections in neonatal and intensive care unit patients. While fluconazole and echinocandins are considered effective treatment of such infections, recent reports of fluconazole and echinocandin resistance in C. parapsilosis indicate a growing problem. The present study describes a novel mechanism of antifungal resistance in this organism affecting the susceptibility of azole and echinocandin antifungals in a clinical isolate obtained from a patient with prosthetic valve endocarditis...
June 19, 2017: Antimicrobial Agents and Chemotherapy
https://www.readbyqxmd.com/read/28630170/characterization-of-aortic-valve-closure-artifact-during-outflow-tract-mapping-correlation-with-hemodynamics-and-mechanical-valves
#10
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/28629843/implanting-a-mechanical-valve-in-the-pulmonary-position-what-s-your-bias
#11
EDITORIAL
Erle H Austin
No abstract text is available yet for this article.
May 18, 2017: Journal of Thoracic and Cardiovascular Surgery
https://www.readbyqxmd.com/read/28626146/mitral-valve-structure-in-addition-to-myocardial-viability-determines-the-outcome-of-functional-mitral-regurgitation-after-coronary-artery-bypass-grafting
#12
Shohei Yoshida, Satsuki Fukushima, Shigeru Miyagawa, Teruya Nakamura, Yasushi Yoshikawa, Hiroki Hata, Shunsuke Saito, Daisuke Yoshioka, Keitaro Domae, Noriyuki Kashiyama, Kouji Yamamoto, Ayumi Shintani, Satoshi Nakatani, Koichi Toda, Yoshiki Sawa
BACKGROUND: Coronary artery bypass grafting (CABG) reduces functional mitral regurgitation (MR) associated with ischemic heart disease, although the predictive factors or mechanisms of reversibility of functional MR after CABG are not fully understood.We investigated whether mitral valve structure is associated with the outcome of functional MR after CABG.Methods and Results:From a consecutive series of 98 patients with mild-moderate functional MR preoperatively who underwent isolated CABG, we enrolled 66 patients who were followed up for >1 year postoperatively using echocardiography...
June 16, 2017: Circulation Journal: Official Journal of the Japanese Circulation Society
https://www.readbyqxmd.com/read/28623503/investigating-the-suitability-of-carbon-nanotube-reinforced-polymer-in-transcatheter-valve-applications
#13
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
#14
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
#15
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
#16
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
#17
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/28615887/an-unusual-cause-of-chest-discomfort-case-report-of-oesophageal-hirudiniasis
#18
Cristóvão Figueiredo, Joana Alves, Cláudia Carvalho, António Sarmento
Hirudiniasis is caused by sanguivorous leeches feeding on mucous membranes with possible severe obstructive or haemorrhagic manifestations. Few cases have been reported in humans, and most occur in tropical countries. A seventy-year-old female patient presented to our Emergency Department (ED) with retrosternal discomfort. She was taking warfarin for a mechanical prosthetic heart valve. While in the ED, a leech was spontaneously extruded from her mouth, with symptomatic resolution. Endoscopy revealed an area of previous leech attachment in the distal oesophageal, without severe bleeding...
June 2017: Journal of Parasitic Diseases: Official Organ of the Indian Society for Parasitology
https://www.readbyqxmd.com/read/28610762/early-trifecta-valve-failure-report-of-a-cluster-of-cases-from-a-tertiary-care-referral-center
#19
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/28610465/successful-truncal-valve-replacement-with-a-mechanical-valve-after-bilateral-pulmonary-artery-banding
#20
Shuichi Yoshitake, Yukihiro Kaneko, Kazuki Yakuwa, Ikuya Achiwa
Surgical management of truncus arteriosus, or common arterial trunk, has expanded over the past three decades to include earlier surgical intervention, initially during infancy and now chiefly in the neonatal period. Many studies have shown that preoperative truncal valve insufficiency is an independent risk factor for mortality. We herein present the case of a five-month-old boy with severe truncal valve insufficiency who underwent repair of common arterial trunk and prosthetic replacement of the truncal valve with associated annular enlargement after initial stabilization in the newborn period via palliative bilateral pulmonary artery banding...
January 1, 2017: World Journal for Pediatric & Congenital Heart Surgery
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