... AccessEditorialPDF/EPUBCould It Happen Again?The Björk-Shiley Convexo-Concave Heart Valve Story Eugene H. Blackstone, MD ... To reduce this tendency, the company developed a convexo-concave disc called the BSCC valve (the original ... Welding metallurgy's putative influence on Bjork-Shiley convexo-concave valve outlet strut failures. J Heart Valve ... JG. Strut fracture mechanisms of the Bjork-Shiley convexo-concave heart valve. J Heart Valve Dis. 1999; ... radiographic systems in the detection of Bjork-Shiley convexo-concave heart valve outlet strut single leg separations. ...
Tópico(s): Statistical Methods in Clinical Trials
2005 - Lippincott Williams & Wilkins | Circulation
In the new convexo-concave model of the Björk-Shiley prosthesis the disc pivots 2.5 mm downstream, creating a space between the ... min for the full flow orifice of the convexo-concave prosthesis was in average 16% lower than ... to 30% (S.D.±2.4) for the convexo-concave model (p < 0.001). The minimum steady flow rate required to maintain the convexo-concave disc in completely open position (60 ml/ ... and was slightly but definitely lower with the convexo-concave model than with standard model. The main ... is concluded that the flow dynamics of the convexo-concave model Björk-Shiley prosthesis constitute a significant ...
Tópico(s): Stroke Rehabilitation and Recovery
1979 - Taylor & Francis | Scandinavian Journal of Thoracic and Cardiovascular Surgery
Dan Lindblom, Viking Olov Björk, Bjarne K. H. Semb,
... valves (n = 430) fractured. Among the 1,461 convexo-concave valves, 18 fractured (6/884 with an ... limit of 1.2%) for the 60 degree convexo-concave valve and 2.8% (upper 95% confidence limit of 4.4%) for the 70 degree convexo-concave valve (p less than 0.01). Two ... this complication; the 23 mm aortic 60 degree convexo-concave valve (5 year actuarial incidence 2.2%, ... the 29 to 31 mm mitral 70 degree convexo-concave valve (8.3%, upper 95% confidence limit ... hazard function presently indicates a constant (60 degree convexo-concave) or decreasing (70 degree convexo-concave) tendency ...
Tópico(s): Transplantation: Methods and Outcomes
1986 - Elsevier BV | Journal of Thoracic and Cardiovascular Surgery
Marjon Kallewaard, Ale Algra, J. Defauw, Yolanda van der Graaf,
... of large (≥29 mm) 60-degree Björk-Shiley convexo-concave mitral valves when it comes to decision ... association between the manufacturing process of Björk-Shiley convexo-concave valves and the risk of fracture has ... of fracture of large 60-degree Björk-Shiley convexo-concave mitral valves. Methods: All Dutch recipients (n = 2264) of Björk-Shiley convexo-concave valves were followed up until fracture, death, ... manufacturing records of large 60-degree Björk-Shiley convexo- concave mitral valves (n = 655) in Dutch recipients ...
Tópico(s): Cardiac Structural Anomalies and Repair
1999 - Elsevier BV | Journal of Thoracic and Cardiovascular Surgery
Babulal Sethia, M. A. Turner, Steven Lewis, R.A. Rodger, W H Bain, Nicholas T. Kouchoukos,
... multiple valve replacement Between 1980 and 1984, 551 convexo-concave valves were implanted in 442 patients: 125 ... was 10.4% and for patients with the convexo-concave prosthesis, 7.0%. Cumulative follow-up extends ... 4 to 14 years (mean 5.2 years); convexo-concave group 747 patient-years, range 1.5 ... disc group 2.9% per patient-year and convexo-concave group 4.3% per patient year (no ... most major complications between the standard disc and convexo-concave prostheses apart from the occurrence of mitral ... outlet strut fracture (p < 0.005) in the convexo-concave group. These results confirm the excellent long- ...
Tópico(s): Cardiac Structural Anomalies and Repair
1986 - Elsevier BV | Journal of Thoracic and Cardiovascular Surgery
Kenneth D. Hopper, Ian C. Gilchrist, J. Richard Landis, Amir H. Abolfathi, A. Russell Localio, Ronald P. Wilson, Walter E. Pae, Allen R. Kunselman, David W. Wieting, James W. Griffith, William S. Pierce, Paul S. Potok, Thomas R. TenHave, James G. Chandler,
... broken outlet struts in normally functioning Björk-Shiley convexo-concave heart valves. Almost all such valves were ... radiographic technique in sheep implanted with known-status convexo-concave valves, comparing its accuracy and that of ... radiography system. Methods: Twenty-one sheep with mitral convexo-concave valves were studied on both systems. Five ... support the need for more intensive training for convexo-concave valve imaging and further investigation of unconventional radiographic technologies. Clinical cineradiography of convexo-concave valves may detect as little as 25% ...
Tópico(s): Mechanical Circulatory Support Devices
1998 - Elsevier BV | Journal of Thoracic and Cardiovascular Surgery
... and narrow aortic annulus, operated upon with the convexo-concave Björk-Shiley prosthesis. The 21 mm prosthesis ... mean systolic pressure difference across the 21 mm convexo-concave prosthesis was 16.2±8.1 mm ... exercise (34±15 watts) across the 23 mm convexo-concave prosthesis. Compared with the earlier investigated standard model Björk-Shiley prosthesis, the 21 mm convexo-concave version creates a lower resistance to blood ...
Tópico(s): Congenital Heart Disease Studies
1981 - Taylor & Francis | Scandinavian Journal of Thoracic and Cardiovascular Surgery
Takashi Iwamoto, Yohki Hieda, Yasumichi Kogai,
... morphology of the HAp materials was flat or convexo-concave, respectively. The flat surface morphology, which showed ... of HAp nanoparticles. On the other hand, the convexo-concave surface morphology resulted from the agglomeration of ... cell adhesion to HAp materials with flat or convexo-concave surface morphology and found that cells adhered ... the flat HAp materials but not to the convexo-concave HAp materials. This technique for selectively preparing HAp materials with flat or convexo-concave surface morphology was very easy because we ...
Tópico(s): 3D Printing in Biomedical Research
2016 - Elsevier BV | Materials Science and Engineering C
Marjon Kallewaard, Ale Algra, J. Defauw, Yolanda der Graaf,
Prophylactic replacement of Björk-Shiley convexo-concave valves (Shiley, Inc., Irvine, Calif.) has been advised for selected groups of patients. If prophylactic replacement is considered, risks of ... the results of prophylactic replacement of Björk-Shiley convexo-concave valves at risk of strut fracture in ... patients undergoing prophylactic replacement of their Björk-Shiley convexo-concave valves before August 1995. Replacement was judged ... 70-degree and 16 60-degree Björk-Shiley convexo-concave valves and one spherical valve were replaced ( ...
Tópico(s): Congenital Heart Disease Studies
1998 - Elsevier BV | Journal of Thoracic and Cardiovascular Surgery
Ajit P. Yoganathan, H. H. Reamer, W. H. Corcoran, Earl C. Harrison,
... hope of reducing these pathologic conditions the new convexo-concave Björk–Shiley prosthesis was developed. In vitro ... anemometer in the immediate downstream vicinity of the convexo-concave Björk–Shiley aortic valve indicate that the ... tissue overgrowth may be reduced in the new convexo-concave Björk – Shiley aortic valve.
Tópico(s): Aortic Disease and Treatment Approaches
1980 - Taylor & Francis | Scandinavian Journal of Thoracic and Cardiovascular Surgery
Kevin C. Dellsperger, David W. Wieting, Debra A. Baehr, Robert Bard, Jean-Pierre Brugger, Earl C. Harrison,
... Jude Medical, Björk-Shiley Spherical Disc, Björk-Shiley Convexo Concave, and Starr-Edwards model 1260—were studied ... min, to 37.5% for the Björk-Shiley Convexo Concave valve at 140 beats/min and 2 ... Jude Medical, Björk-Shiley Spherical Disc, Björk-Shiley Convexo Concave, and Starr-Edwards model 1260—were studied ... min, to 37.5% for the Björk-Shiley Convexo Concave valve at 140 beats/min and 2 ...
Tópico(s): Aortic Disease and Treatment Approaches
1983 - Elsevier BV | The American Journal of Cardiology
J. Ostermeyer, Dieter Horstkotte, J.A. Bennett, Hans A. Huysmans, Dan Lindblom, Christian Olin, E. Orinius, Gudmund Semb,
... and June 1983 4028 Björk-Shiley 70 degree convexo-concave prosthetic heart valves were distributed and implanted ... flanges originally machined as Björk-Shiley 60 degree convexo-concave valves (group I) and later produced valves ... 29 mm-33 mm Björk-Shiley 70 degree convexo-concave valves as the highest risk group for ...
Tópico(s): Infective Endocarditis Diagnosis and Management
1987 - Georg Thieme Verlag | The Thoracic and Cardiovascular Surgeon
Jan van der Meulen, Ewout W. Steyerberg, Yolanda van der Graaf, Lex A. van Herwerden, C J Verbaan, J. Defauw, J. Dik F. Habbema,
BACKGROUND Björk-Shiley convexo-concave heart valves have an increased risk of mechanical failure. One might consider prophylactic rereplacement as a preventive measure ... on type and position of the Björk-Shiley convexo-concave heart valve and rise steeply as the ... guidance for prophylactic replacement of the Björk-Shiley convexo-concave valve on an individual basis. Rereplacement compares ...
Tópico(s): Healthcare Policy and Management
1993 - Lippincott Williams & Wilkins | Circulation
Jarmo Gunn, Markus Malmberg, Tommi Vähäsilta, Anne Lahti, Kari Kuttila,
... prosthesis have shown good long-term results. The convexo-concave model, however, was recalled 27 years ago ... year outcome after implantation of the Björk-Shiley convexo-concave mechanical heart valve prosthesis (Pfizer, Rye Brook, ... possibility of structural valve failure the Björk-Shiley convexo-concave valve confers excellent 30-year survival.
Tópico(s): Aortic Disease and Treatment Approaches
2013 - Elsevier BV | The Annals of Thoracic Surgery
Dana M. Stevenson, Ajit P. Yoganathan, Robert H. Franch,
... the hope of reducing these pathologic conditions the convexo-concave Björk-Shiley valve was designed. A new modification to the convexo-concave model has further improved most of the ... in the immediate downstream vicinity of the modified convexo-concave valve indicate that the design changes have ...
Tópico(s): Cardiovascular Function and Risk Factors
1982 - Taylor & Francis | Scandinavian Journal of Thoracic and Cardiovascular Surgery
Loren F. Hiratzka, Nicholas T. Kouchoukos, Gary L. Grunkemeier, D. Craig Miller, Hugh E. Scully, Andrew S. Wechsler,
... outlet strut fracture of the Björk-Shiley 60 ° Convexo-Concave tilting disc prosthesis has received much attention ... explantation of a well functioning Björk-Shiley 60 ° Convexo-Concave valve prosthesis is not warranted. Diagnostic features ...
Tópico(s): Cardiac Structural Anomalies and Repair
1988 - Elsevier BV | Journal of the American College of Cardiology
... Delrin, n = 51; standard pyrolytic carbon, n = 307; convexo-concave with an opening angle of 60 degrees, n = 229; convexo-concave with an opening angle of 70 degrees, ... 0.0005) reduced after the introduction of the convexo-concave valves, and this reduction was achieved without ...
Tópico(s): Infective Endocarditis Diagnosis and Management
1988 - Elsevier BV | Journal of Thoracic and Cardiovascular Surgery
... the risk. The story of the Bjork-Shiley Convexo-Concave heart valve is a case in point. ... The recent failure of hundreds of Bjork-Shiley Convexo-Concave (C/C) mechanical heart valves provides a ... Shiley introduced a similar valve, the 60[degrees] Convexo-Concave (C/C), which they believed would improve ...
Tópico(s): Biotechnology and Related Fields
1993 - Wiley | The Hastings Center Report
Thomas A. Orszulak, Hartzell V. Schaff, Jean-Marie DeSmet, Gordon K. Danielson, James R. Pluth, Francisco J. Puga,
... including valve position and valve model (spherical versus convexo-concave discs). No valve failure due to strut ... risk of valve thrombosis comparing the spherical and convexo-concave discs (0.27 per 100 patient-years ... in the rates of thromboemboli for spherical and convexo-concave discs for all patients and for each ...
Tópico(s): Cardiac Structural Anomalies and Repair
1993 - Elsevier BV | Journal of Thoracic and Cardiovascular Surgery
Ewout W. Steyerberg, Jan van der Meulen, Lex A. van Herwerden, J. Dik F. Habbema,
... decision-making on prophylactic replacement of Björk-Shiley convexo-concave heart valves. DESIGN: Decision analysis comparing elective ... is likely with replacement of a Björk-Shiley convexo-concave heart valve. It can be used to ...
Tópico(s): Cardiovascular Function and Risk Factors
1996 - BMJ | Heart
Donald C. Harrison, Michel Ibrahim, Arthur E. Weyman, Lewis H. Kuller, William J. Blot, David E. Miller,
... Pfizer class action suit involving the Björk-Shiley convexo-concave (BSCC) heart valve are detailed. Of approximately ... the struts, and structural analyses of Björk-Shiley convexo-concave valves, but none proved applicable for large- ...
Tópico(s): Healthcare Policy and Management
2013 - Elsevier BV | The American Journal of Cardiology
Rumana Z. Omar, L Morton, M T Beirne, William J. Blot, Patricia V. Lawford, Rodney Hose, Kenneth M. Taylor,
Background: Björk-Shiley 60° convexo-concave prosthetic heart valves (Shiley, Inc, Irvine, Calif, a subsidiary of Pfizer, Inc) continue to be a concern for approximately ... responsible for outlet strut fractures of Björk-Shiley convexo-concave valves. Multiple hook deflection tests have emerged ...
Tópico(s): Transplantation: Methods and Outcomes
2001 - Elsevier BV | Journal of Thoracic and Cardiovascular Surgery
Shin Ishimaru, Kinichi Furuawka, Masatoshi Takahashi,
The in vivo function of the convexo-concave Björk-Shiley prosthetic valve implanted in mitral position was evaluated with a simple cineradiographic procedure. The maximum opening angle of the ... observed in all patients. Excellent function of the convexo-concave Björk-Shiley prosthesis was demonstrated by cineradiography. ...
Tópico(s): Cardiac Arrhythmias and Treatments
1983 - Taylor & Francis | Scandinavian Journal of Thoracic and Cardiovascular Surgery
Produção Nacional
Rudimar Luiz Nós, Victoria Mazotti Rodrigues da Silva,
... duas estratégias para calcular o volume de poliedros convexos: a decomposição do poliedro em poliedros de volume ... dinâmica GeoGebra 3D para a construção de poliedros convexos e também para as composições/decomposições. Concluı́mos que ... estratégias para o cálculo do volume de poliedros convexos.
Tópico(s): 3D Modeling in Geospatial Applications
2020 - | Proceeding Series of the Brazilian Society of Computational and Applied Mathematics
Ajit P. Yoganathan, Dana M. Stevenson, Frank P. Williams, Yi‐Ren Woo, Robert H. Franch, Earl C. Harrison,
... drop characteristics compared to the Lillehei-Kaster and convexo-concave Björk-Shiley (60° model) tilting disc valves. ... of the Medtronic-Hall valve, compared to the convexo-concave Björk-Shiley (60° model) and Lillehei-Kaster ...
Tópico(s): Cardiac Arrhythmias and Treatments
1982 - Taylor & Francis | Scandinavian Journal of Thoracic and Cardiovascular Surgery
L Bergdahl, Viking Olov Björk, Rune Jonasson,
... was implanted in 15 cases and the new convexo-concave model in 12 cases. Sixty-seven per ... absolute contra-indication for aortic valve replacement. The convexo-concave Björk-Shiley tilting disc prosthesis is suitable ...
Tópico(s): Infective Endocarditis Diagnosis and Management
1981 - Taylor & Francis | Scandinavian Journal of Thoracic and Cardiovascular Surgery
Gerard L. Guit, A E van Voorthuisen, Robert M. Steiner,
... analysis of normal and bimodal Björk-Shiley 60 ° convexo-concave heart valvesGerald A.Kien, BradleyJeffries, Hart V. ... 3Outlet strut fracture of the Björk-Shiley 60 ° Convexo-Concave valve: Current information and recommendations for patient ...
Tópico(s): Cardiac Structural Anomalies and Repair
1985 - Radiological Society of North America | Radiology
... be derived from several different processes. For example, convexo‐concave forms develop under soil creep with basal ...
Tópico(s): Geotechnical Engineering and Analysis
1987 - Wiley | Earth Surface Processes and Landforms
José Cortina, J. Martinell, V. Artiz, J. Fraile, Gregorio Rábago,
... the Medtronic-Hall valve, and 60 patients the convexo-concave 70 degree Björk-Shiley prosthesis. Hospital mortality ...
Tópico(s): Aortic Disease and Treatment Approaches
1986 - Elsevier BV | Journal of Thoracic and Cardiovascular Surgery
Produção Nacional
Revisado por pares
Maria Amélia Cesari Quaglia, Sérgio Sheiji Fukusima,
... invertida, iluminado por baixo) como côncavos, planos ou convexos. Além disso, as magnitudes dos seus relevos percebidos ... que os reversos das máscaras foram percebidos como convexos. E mesmo nas poucas respostas em que as ...
Tópico(s): Evolutionary Psychology and Human Behavior
2009 - UNIVERSIDADE FEDERAL DO RIO GRANDE DO NORTE | Estudos de Psicologia (Natal)