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Mitral heart valve frame design

Benyamin Rahmani, Spyros Tzamtzis, Rose Sheridan, Michael J Mullen, John Yap, Alexander M Seifalian, Gaetano Burriesci
AIMS: The aim of this study was to introduce and demonstrate the feasibility in an acute preclinical model of a new transcatheter heart valve concept with a self-expanding wire frame, polymeric leaflets and a sealing component. METHODS AND RESULTS: The TRISKELE valve was developed based on a previously validated polymeric leaflet design, an adaptive sealing cuff and a novel nitinol wire frame which reduces stress on the leaflets and radial pressure on the surrounding tissue...
September 18, 2016: EuroIntervention
Cesare Quarto, Simon Davies, Alison Duncan, Alistair Lindsay, Georg Lutter, Lucian Lozonschi, Neil Moat
OBJECTIVE: A small number of transcatheter mitral valve implants (TMVIs) have been reported using devices designed to treat secondary mitral regurgitation (MR). However, MR has many etiologies, and patients have a broad spectrum of annular size, geometry, and lesions. There are a number of technical challenges for TMVI including left ventricular outflow tract obstruction and paravalvular MR. Thirty days' outcome of first-in-man implants with a novel TMVI device is reported. METHODS: The Tendyne TMVI system consists of a porcine pericardial valve in a tethered nitinol frame...
May 2016: Innovations: Technology and Techniques in Cardiothoracic and Vascular Surgery
Melissa Young, Ahmet Erdemir, Samantha Stucke, Ryan Klatte, Brian Davis, Jose L Navia
In certain populations, open heart surgery to replace a diseased mitral valve is not an option, leaving percutaneous delivery a viable alternative. However, a surgical transcatheter based delivery of a metallic support frame incorporating a tissue derived valve puts considerable constraints on device specifications. Expansion to a large diameter from the catheter diameter without mechanical fracture involves advanced device design and appropriate material processing and selection. In this study, a new frame concept is presented with a desirable feature that incorporates wings that protrude during expansion to establish adequate fixation...
September 2012: Journal of Medical Devices
Murray Legg, Edward Mathews, Ruaan Pelzer
A study was conducted into the development of a mitral and aortic heart valve replacement that caters for patients having suffered valve damage due to stenosis or rheumatic fever. The appeal of the valve is that it is constituted from a solid frame housing pericardial tissue leaflets, and allows the patient freedom from post-operative blood-thinning medication. The valve is designed to appeal to patients in developing areas of the world, as it features a clip-in mechanism to secure the valve assembly into the sewing ring, which is stitched in independently of the frame and leaflets...
April 2012: Cardiovascular Journal of Africa
S Göktepe, W Bothe, J-P E Kvitting, J C Swanson, N B Ingels, D C Miller, Ellen Kuhl
The implantation of annuloplasty rings is a common surgical treatment targeted to re-establish mitral valve competence in patients with mitral regurgitation. It is hypothesized that annuloplasty ring implantation influences leaflet curvature, which in turn may considerably impair repair durability. This research is driven by the vision to design repair devices that optimize leaflet curvature to reduce valvular stress. In pursuit of this goal, the objective of this manuscript is to quantify leaflet curvature in ovine models with and without annuloplasty ring using in vivo animal data from videofluoroscopic marker analysis...
June 2010: Biomechanics and Modeling in Mechanobiology
Athar M Qureshi, Muhammad A Mumtaz, Larry A Latson
One or more breaks in the wire frame of the HELEX Septal Occluder (W.L. Gore and Associates, Flaggstaff, Arizona) were identified in 5% of patients in the multicenter pivotal trial leading to FDA approval. Fractures of the perimeter frame have not previously been associated with any apparent deleterious clinical effects. We report a case in which the broken ends of wire at a frame fracture were located in a position that resulted in perforation of the anterior mitral valve leaflet. There was significant mitral regurgitation and the device was removed surgically...
November 1, 2009: Catheterization and Cardiovascular Interventions
Shao-Wei Chen, Feng-Chun Tsai, Feng-Chang Tsai, Chun-Chi Chen, Chun-Li Wang, Mon-Yue Wu, Yao-Kuang Huang, Jaw-Ji Chu, Pyng Jing Lin
BACKGROUND: The success rate of mitral annuloplasty (MA) for functional mitral regurgitation (FMR) varies. This study evaluated the effectiveness of this procedure in nonischemic dilated cardiomyopathy (DCM) patients after a selective treatment protocol was followed. METHODS AND RESULTS: This study analyzed 42 patients with nonischemic DCM and FMR (mean regurgitation grade, 3.6 +/- 0.3), aged a mean 56.5 +/- 15 years (range, 25 to 78 years), who underwent MA from April 2003 to December 2007...
May 2009: Journal of Cardiac Failure
William J Blot, Lisa B Signorello, Sarah S Cohen, Michel A Ibrahim
BACKGROUND AND AIM OF THE STUDY: Björk-Shiley convexo-concave (BSCC) prosthetic heart valves are believed to have been implanted in over 86,000 patients worldwide. Limited data are available on the prevalence of single leg separations (SLS) of the valves' outlet struts, a potential precursor to complete valve fracture. METHODS: Data maintained by the manufacturer, including results of examinations for SLS in explanted valves, were merged with available information on the characteristics of the valve...
November 2007: Journal of Heart Valve Disease
Gino Gerosa, Riccardo Carta, Massimo Montisci, Loira Leoni, Sabino Iliceto, Giulio Rizzoli, Francesca di Marco
BACKGROUND: TRI Technologies (TT) valves evidenced a propensity to structural failure, consisting in fracture of the pivoting system, leading to leaflet escape. At our institution, between 2000 and 2002, 36 TT valves were implanted in 34 patients. Here we report the final results of the Tritech survey program. METHODS: In February 2002, the first valve-related death occurred. After the event, patients were enrolled in the TT valve survey program and strictly followed up...
September 2006: Annals of Thoracic Surgery
Dusan Pavcnik, John A Kaufman, Barry T Uchida, Brian Case, Luiz O Correa, Ahmet Yigit Goktay, Ayumi Hamada, Frederick S Keller, Josef Rösch
PURPOSE: To investigate two spatial orientations of a percutaneously placed bicuspid second-generation bioprosthetic venous valve (SG-BVV) in the jugular vein (JV). MATERIALS AND METHODS: Twelve SG-BVVs, consisting of small intestinal submucosa attached to a nitinol frame were placed across a natural valve (NV) in the distal JV in six sheep. Six SG-BVVs were oriented as NV leaflets (group A) and the other six SG-BVVs were rotated 90 degrees to NV leaflets (group B)...
November 2005: Journal of Vascular and Interventional Radiology: JVIR
Jan Aagaard, Jens Tingleff
BACKGROUND AND AIM OF THE STUDY: The CarboMedics bileaflet prosthetic heart valve was first implanted as part of a prospective clinical study at the authors' institution in November 1987. The patient cohort included was part of a multicenter trial set up by the manufacturer for an FDA application. The present report details findings over a 15-year period, with a continuous follow up on this patient cohort. METHODS: Between November 1987 and August 1990, 132 patients (68 males, 64 females; median age 56 years; range: 12-74 years) received a CarboMedics heart valve prosthesis...
January 2005: Journal of Heart Valve Disease
Ram Sharony, Paul C Saunders, Ambika Nayar, Eileen McAleer, Aubrey C Galloway, Julie Delianides, Charles F Schwartz, Robert M Applebaum, Itzhak Kronzon, Stephen B Colvin, Eugene A Grossi
BACKGROUND: Traditional mitral annuloplasty devices include both rigid rings, which restrict annular motion, and soft rings and bands, which can locally deform. Conflicting data exist regarding their impact on annular dynamics. We studied mitral annuloplasty with a semirigid partial band and with a nearly complete rigid ring. METHODS: Intraoperative three-dimensional transesophageal echocardiograms (n = 14) and predischarge transthoracic echocardiograms were retrospectively analyzed in patients undergoing mitral valve repair for degenerative disease with either a rigid ring (n = 77) or a semirigid partial band (n = 38)...
February 2004: Annals of Thoracic Surgery
Simcha Milo, Chaim Gutfinger, Gina Yu-chi Chu, Morteza Gharib
BACKGROUND AND AIM OF THE STUDY: Bubble formation in blood, which has been observed during valve closure in patients with mechanical heart valves (MHVs), raises concern because of cognitive changes and potential activation of blood elements associated with thromboembolic phenomena. Bubble formation in the vicinity of MHVs has been described previously; the present in-vitro study was undertaken to quantitate bubbles leaving the heart and entering the systemic circulation, and to gain a closer perspective of this phenomenon and its potential clinical implications...
May 2003: Journal of Heart Valve Disease
S R Kaplan, G Bashein, F H Sheehan, M E Legget, B Munt, X N Li, M Sivarajan, E L Bolson, M Zeppa, M Z Arch, R W Martin
OBJECTIVES: To compare mitral annular shape and motion throughout the cardiac cycle in patients with normal hearts versus those with functional mitral regurgitation (FMR). BACKGROUND: The causes of mitral regurgitation without valvular disease are unclear, but the condition is associated with changes in annular shape and dynamics. Three-dimensional (3D) imaging provides a more comprehensive view of annular structure and allows accurate reconstructions at high spatial and temporal resolution...
March 2000: American Heart Journal
K A Powell, N A Obuchowski, A C Yeung, J A Kennedy, J F Cornhill
BACKGROUND AND AIM OF THE STUDY: The study goal was to determine whether the visualization of single-leg separation (SLS) in cineangiographic sequences of Björk-Shiley convexo-concave heart valves could be correlated to the position of the occluder disk within the cardiac cycle. METHODS: Images from ten patient cases with SLS valves were reviewed by three experts, who identified the image frames within a cine sequence that appeared suspicious for SLS. The position of the occluder disk, the frame rate, and the length of the cardiac cycle were noted relative to these image frames...
July 1999: Journal of Heart Valve Disease
L J Quintero, J M Lohre, N Hernandez, S C Meyer, T J McCarthy, D S Lin, S H Shen
BACKGROUND AND AIM OF THE STUDY: A common frame of reference is essential when attempting to determine if new treatments intended to reduce calcification of bioprostheses are superior to existing processes and products. The aim of this study was to examine calcification behavior for a commercially available pericardial bioprosthesis in subcutaneous and sheep valve models, and to evaluate the importance of appropriate control treatments in comparative studies with proposed new treatments...
May 1998: Journal of Heart Valve Disease
J Corden, T David, J Fisher
In vitro velocity data were obtained downstream of two versions of the Leeds polyurethane trileaflet heart valve in a simulated pulsatile flow regime using laser Doppler velocimetry. The main difference between the two valves studied was the manufacturing method used to create the valves. The film-fabricated valve was constructed from solvent-cast sheets of polyurethane, thermally formed into the correct leaflet geometry. The dip-cast valve used a stainless steel mould which was dipped into a polyurethane solution to produce the valve leaflets...
1996: Proceedings of the Institution of Mechanical Engineers. Part H, Journal of Engineering in Medicine
T Aoyagi, H Pouleur, C Van Eyll, M F Rousseau, I Mirsky
Left ventricular (LV) diastolic filling is impaired in hearts with healed myocardial infarction. Possible hemodynamic parameters related to impaired LV filling include left atrial pressure, time constant of isovolumic relaxation, chamber stiffness and wall motion asynchrony. Previous studies demonstrated univariate correlations between each of these parameters and LV filling. The current study was designed to compare relative importance of these parameters in patients with a myocardial infarction. Left ventriculograms with simultaneous LV pressure measurement were analyzed in 15 patients with a myocardial infarction and in 10 control subjects...
August 1, 1993: American Journal of Cardiology
H von Bibra, H Becher, C Firschke, R Schlief, H P Emslander, A Schömig
OBJECTIVES: The saccharide ultrasound contrast agent SHU 508 A was used to test the hypothesis that an intravenous, transpulmonary contrast method can enhance color Doppler flow signals in the left atrium in a clinically useful manner. BACKGROUND: Color Doppler display of mitral regurgitation may be unreliable because of variable signal to noise ratios that are at times poor. Traditional contrast agents enhance color Doppler flow signals in the right heart chambers...
August 1993: Journal of the American College of Cardiology
S L Dzemeshkevich, B A Konstantinov, G V Gromova, R A Lyudinovskova, L L Kudrina
The BAKS bioprostheses were created in our centre and they have the following features: (1) to reduce immunogenicity they underwent a combined fermentochemical treatment which resulted in the native xenovalve consisting of collagen and elastic fibres only; (2) in cutting out the valve the natural aortic sinuses were preserved; and (3) the xenovalve was fixed on a functional frame of an original design. From 1979, BAKS have been implanted in 243 patients with the isolated mitral valve reumatic injury. The patients age varied from 11 to 59 years; 91 patients (37...
December 1994: Journal of Cardiovascular Surgery
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