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mechanical valve prostheses

Anthony P Carnicelli, Patrick T O'Gara, Robert P Giugliano
Valvular heart disease is prevalent and represents a significant contributor to cardiac morbidity and mortality. Several options for valve replacement exist, including surgical replacement and transcatheter valve implantation. Prosthetic valves lead to increased risk of thromboembolic disease; therefore, antithrombotic therapy after valve replacement is indicated. For patients with mechanical prostheses, indefinite vitamin K antagonist and antiplatelet therapy are the mainstays of treatment. There is no consensus regarding optimal antithrombotic therapy after bioprosthetic valve replacement, although vitamin K antagonist therapy of varying duration in addition to antiplatelet therapy is recommended by guidelines...
August 13, 2016: American Journal of Cardiology
Ana Redondo Palacios, José López Menéndez, Javier Miguelena Hycka, Miren Martín García, Laura Varela Barca, Andrea Ferreiro Marzal, Rafael Muñoz Pérez, Enrique Oliva De Anquín, Ignacio García Andrade, Tomasa Centella Hernández, Daniel Celemín Canorea, Jorge Rodríguez-Roda Stuart
BACKGROUND: Nowadays, Tricuspid valve replacement (TVR) is much less common than aortic or mitral valve replacement, since repair is almost always preferable. Prosthetic tricuspid valves are associated with high mortality and morbidity, mostly due to thrombotic or hemorrhagic events. Nevertheless, there is lack of evidence of which is the optimal type of valve (biological versus mechanical) in tricuspid position. METHODS: We analysed all the patients who underwent TVR in our Institution, from 2005 to 2015...
September 16, 2016: Journal of Cardiovascular Surgery
Amir Basir, Paul Gründeman, Frans Moll, Joost van Herwaarden, Gerard Pasterkamp, Reindert Nijland
Various materials that are used for vascular and heart valve prostheses carry drawbacks: some require anticoagulant drugs or have moderate durability; others are not suitable for endovascular treatment. These prostheses are associated with bacterial infections. A material potentially suitable for prostheses is Dyneema Purity®, made of ultra-high-molecular-weight polyethylene. Dyneema Purity® fibers are very thin, flexible, resistant to fatigue and abrasion, and have high strength. S. aureus adherence to Dyneema Purity® was tested and compared with currently used cardiovascular prostheses...
2016: PloS One
Yaghoub Dabiri, Janet Ronsky, Imtiaz Ali, Ameen Basha, Alisha Bhanji, Kishan Narine
Bioprosthetic aortic valves (BAVs) are becoming the prostheses of choice in heart valve replacement. The objective of this paper is to assess the effects of leaflet geometry on the mechanics and hemodynamics of BAVs in a fluid structure interaction model. The curvature and angle of leaflets were varied in 10 case studies whereby the following design parameters were altered: a circular arch, a line, and a parabola for the radial curvature, and a circular arch, a spline, and a parabola for the circumferential curvature...
August 29, 2016: Cardiovascular Engineering and Technology
Costantino Del Gaudio, Pier Luca Gasbarroni, Giovanni Paolo Romano
End-stage failing heart valves are currently replaced by mechanical or biological prostheses. Both types positively contribute to restore the physiological function of native valves, but a number of drawbacks limits the expected performances. In order to improve the outcome, tissue engineering can offer an alternative approach to design and fabricate innovative heart valves capable to support the requested function and to promote the formation of a novel, viable and correctly operating physiological structure...
December 2016: Journal of the Mechanical Behavior of Biomedical Materials
Kristina Wachter, Samir Ahad, Christian J Rustenbach, Ulrich F W Franke, Hardy Baumbach
BACKGROUND: Transcatheter aortic valve implantation (TAVI) has proven to be a valid option for patients with severe aortic stenosis who are at high perioperative risk, particularly in patients with previous cardiac surgery. Several patients with previous mitral valve surgery were reported to have been successfully treated with TAVI. CASE PRESENTATION: Two patients, one with mechanical and one with biological mitral valve prosthesis, presented with symptomatic severe aortic stenosis...
2016: Journal of Cardiothoracic Surgery
M G C Nestola, E Faggiano, C Vergara, R M Lancellotti, S Ippolito, C Antona, S Filippi, A Quarteroni, R Scrofani
We provide a computational comparison of the performance of stentless and stented aortic prostheses, in terms of aortic root displacements and internal stresses. To this aim, we consider three real patients; for each of them, we draw the two prostheses configurations, which are characterized by different mechanical properties and we also consider the native configuration. For each of these scenarios, we solve the fluid-structure interaction problem arising between blood and aortic root, through Finite Elements...
July 26, 2016: Computer Methods in Biomechanics and Biomedical Engineering
Francesco Nappi, Angelo Rosario Carotenuto, Arsenio Cutolo, Pierre Fouret, Christophe Acar, Juan Carlos Chachques, Massimiliano Fraldi
Synthetic grafts are often satisfactory employed in cardiac and vascular surgery, including expanded poly(ethylene terephthalate) or expanded poly(tetrafluoroethylene). However, accumulating evidences suggest the emergence of worrisome issues concerning the long-term fate of prosthetic grafts as large vessel replacement. Disadvantages related to the use of synthetic grafts can be traced in their inability of mimicking the elasto-mechanical characteristics of the native vascular tissue, local suture overstress leading to several prosthesis-related complications and retrograde deleterious effects on valve competence, cardiac function and perfusion...
October 2016: Journal of the Mechanical Behavior of Biomedical Materials
Domenico Acanfora, Chiara Acanfora, Pietro Scicchitano, Marialaura Longobardi, Giuseppe Furgi, Gerardo Casucci, Bernardo Lanzillo, Ilaria Dentamaro, Annapaola Zito, Raffaele Antonelli Incalzi, Marco Matteo Ciccone
BACKGROUND AND OBJECTIVES: The new oral anticoagulants (NOACs) are used for the prevention of thromboembolic complications in patients with non-valvular atrial fibrillation (AF) and those at risk of deep venous thrombosis. Their rapid onset of action and predictable pharmacokinetic and pharmacodynamic profiles make them the optimal alternative to warfarin in the treatment of these two categories of patients. Unfortunately, however, NOACs cannot be used in patients with valvular AF or valvular cardiac prostheses...
October 2016: Clinical Drug Investigation
Alexander C Egbe, Heidi M Connolly, Joseph T Poterucha, Carole A Warnes
OBJECTIVES: There is a paucity of data about mixed aortic valve disease (MAVD) in patients with bicuspid/unicuspid aortic valve (BAV). This study sought to describe the outcomes of patients with moderate/severe MAVD. METHODS: We queried our database for patients with BAV and moderate/severe MAVD seen between 1994 and 2013. We excluded patients with baseline New York Heart Association (NYHA) III/IV symptoms, left ventricular ejection fraction <50%, aortic dimension >50 mm, and significant disease of other valves...
July 4, 2016: Congenital Heart Disease
Shiv Kumar Choudhary, Sachin Talwar, Balram Airan
Mechanical prostheses and stented xenografts (bioprosthesis) are most commonly used substitutes for aortic and mitral valve replacement. The mechanical valves have the advantage of durability but are accompanied with the risk of thromboembolism, problems of long-term anticoagulation, and associated risk of bleeding. In contrast, bioprosthetic valves do not require long-term anticoagulation, but carry the risk of structural valve degeneration and re-operation. A mechanical valve is favoured in young patients (<40 years) if reliable anticoagulation is ensured...
2016: Heart Asia
Guglielmo Stefanelli, Fabrizio Pirro, Marco Meli, Davide Trevisan, Mariassunta Telesca, Barbara Campisano, Cristina Mussini, Andrea Barbieri
OBJECTIVES: The aim of this study is to evaluate the ease of use and the advantages of Sorin Pericarbon Freedom (SPF) stentless valve in cases of acute bacterial endocarditis and to check the intermediate-term results after the implant of SPF with respect to resistance to infection, valve deterioration and durability. METHODS: Between June 2003 and February 2015, 26 patients with active aortic valve bacterial endocarditis underwent aortic valve replacement with SPF pericardial stentless aortic prosthesis...
October 2016: Interactive Cardiovascular and Thoracic Surgery
Eric J Keller, S Chris Malaisrie, Jane Kruse, Patrick M McCarthy, James C Carr, Michael Markl, Alex J Barker, Jeremy D Collins
OBJECTIVES: Previous work suggests that aortic root and valve prostheses alter blood flow patterns in the ascending aorta, creating aberrant haemodynamics compared with those of healthy volunteers. Various valve designs have been proposed to better restore physiological haemodynamics. In this study, magnetic resonance imaging (MRI) was used to non-invasively assess three-dimensional (3D) ascending aortic haemodynamics after aortic root replacement (ARR) with a mechanical valved conduit postulated to create less turbulent blood flow...
September 2016: Interactive Cardiovascular and Thoracic Surgery
Paul Toon-Lim Chiam, See-Hooi Ewe, Jia-Lin Soon, Kay-Woon Ho, Yong-Koong Sin, Swee-Yaw Tan, Soo-Teik Lim, Tian-Hai Koh, Yeow-Leng Chua
INTRODUCTION: Percutaneous transcatheter aortic valve implantation (TAVI) has become an established therapy for inoperable and high-surgical-risk patients with severe aortic stenosis. Although TAVI in patients with degenerated surgical aortic bioprostheses (i.e. valve-in-valve TAVI) is increasingly reported in Western studies, such data is lacking in Asian patients. We describe the initial experience of valve-in-valve TAVI in Asia. METHODS: Eight patients who underwent valve-in-valve TAVI due to degenerated aortic bioprostheses were enrolled...
July 2016: Singapore Medical Journal
Kevin Phan, Dong Fang Zhao, Jessie J Zhou, Aran Karagaratnam, Steven Phan, Tristan D Yan
BACKGROUND: Patients with end-stage renal disease (ESRD) indicated for dialysis are increasingly requiring cardiac valve surgery. The choice of bioprosthetic or mechanic valve prosthesis for such patients requires careful risk assessment. A systematic review and meta-analysis was performed to assess current evidence available. METHODS: A comprehensive search from six electronic databases was performed from their inception to February 2015. Results from patients with ESRD undergoing cardiac surgery for bioprosthetic or mechanical valve replacement were identified...
May 2016: Journal of Thoracic Disease
Eric L Pierce, Andrew W Siefert, Deborah M Paul, Sarah K Wells, Charles H Bloodworth, Satoshi Takebayashi, Chikashi Aoki, Morten O Jensen, Matthew J Gillespie, Robert C Gorman, Joseph H Gorman, Ajit P Yoganathan
BACKGROUND: Annuloplasty ring dehiscence is a well described mode of mitral valve repair failure. Defining the mechanisms underlying dehiscence may facilitate its prevention. METHODS: Factors that govern suture dehiscence were examined with an ovine model. After undersized ring annuloplasty in live animals (n = 5), cyclic force (FC) that acts on sutures during cardiac contraction was measured with custom transducers. FC was measured at ten suture positions, throughout cardiac cycles with peak left ventricular pressure (LVPmax) of 100, 125, and 150 mm Hg...
August 2016: Annals of Thoracic Surgery
Manal H El-Hamamsy, Gihan H Elsisi, Randa Eldessouki, Mohamed M Elmazar, Ahmed S Taha, Basma F Awad, Hossam Elmansy
BACKGROUND: The use of combined therapy of antiplatelet and anticoagulant versus anticoagulant alone to reduce instances of thromboembolic events in patients with heart valve prostheses is an established standard of care in many countries but not in Egypt. A previous Markov model cost-effectiveness study on Egyptian patients aged 50-60 years demonstrated that the combined therapy reduces the overall treatment cost. However, due to the lack of actual real-world data on cost-effectiveness and the limitation of the Markov model study to 50- to 60-year-old patients, the Egyptian medical community is still questioning whether the added benefit is worth the cost...
August 2016: Applied Health Economics and Health Policy
L Barbarash, I Kudryavtsev, N Rutkovskaya, A Golovkin
The study was aimed at assessing T cell subsets of peripheral blood from recipients of long-term functioning (more than 60 months) biological and mechanical heart valve prostheses. The absolute and relative number of CD4 and CD8 T cell subsets was analyzed: naïve (N, CD45RA(+)CD62L(+)), central memory (CM, CD45RA(-)CD62L(+)), effector memory (EM, CD45RA(-)CD62L(-)), and terminally differentiated CD45RA-positive effector memory (TEMRA, CD45RA(+)CD62L(-)) in 25 persons with biological and 7 with mechanical prosthesis compared with 48 apparently healthy volunteers...
2016: Mediators of Inflammation
Joon Bum Kim, Julius I Ejiofor, Maroun Yammine, Janice M Camuso, Conor W Walsh, Masahiko Ando, Serguei I Melnitchouk, James D Rawn, Marzia Leacche, Thomas E MacGillivray, Lawrence H Cohn, John G Byrne, Thoralf M Sundt
BACKGROUND: Surgical dogma suggests that homografts should be used preferentially, compared with conventional xenograft or mechanical prostheses, in the setting of infective endocarditis (IE), because they have greater resistance to infection. However, comparative data that support this notion are limited. METHODS: From the prospective databases of 2 tertiary academic centers, we identified 304 consecutive adult patients (age ≥17 years) who underwent surgery for active IE involving the aortic valve (AV), in the period 2002 to 2014...
May 2016: Journal of Thoracic and Cardiovascular Surgery
Sherif W Ayad, Mahmoud M Hassanein, Elsayed A Mohamed, Ahmed M Gohar
BACKGROUND: Pregnancy is associated with several cardiocirculatory changes that can significantly impact underlying cardiac disease. These changes include an increase in cardiac output, sodium, and water retention leading to blood volume expansion, and reductions in systemic vascular resistance and systemic blood pressure. In addition, pregnancy results in a hypercoagulable state that increases the risk of thromboembolic complications. OBJECTIVES: The aim of this study is to assess the maternal and fetal outcomes of pregnant women with mechanical prosthetic heart valves (PHVs)...
2016: Clinical Medicine Insights. Cardiology
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