scholarly journals Valve Type, Size, and Deployment Location Affect Hemodynamics in an In Vitro Valve-in-Valve Model

2016 ◽  
Vol 9 (15) ◽  
pp. 1618-1628 ◽  
Author(s):  
Prem A. Midha ◽  
Vrishank Raghav ◽  
Jose F. Condado ◽  
Ikechukwu U. Okafor ◽  
Stamatios Lerakis ◽  
...  
Keyword(s):  
Type Size ◽  
Valve In Valve ◽  
Valve Model

scholarly journals Intracardiac Visualization of Transcatheter Aortic Valve and Valve-in-Valve Implantation in an In Vitro Passive Beating Heart

2013 ◽  
Vol 6 (1) ◽  
pp. 92-93 ◽  
Author(s):  
Alberto M. Leopaldi ◽  
Riccardo Vismara ◽  
Guido Gelpi ◽  
Claudia Romagnoni ◽  
Gianfranco B. Fiore ◽  
...  
Keyword(s):  
Aortic Valve ◽  
Beating Heart ◽  
Transcatheter Aortic Valve ◽  
Valve In Valve ◽  
Valve Implantation

scholarly journals In vitro study of trileaflet polytetrafluoroethylene conduit and its valve-in-valve transformation

2020 ◽  
Vol 30 (3) ◽  
pp. 408-416 ◽  
Author(s):  
Te-I Chang ◽  
Kang-Hong Hsu ◽  
Chi-Wen Luo ◽  
Jen-Hong Yen ◽  
Po-Chien Lu ◽  
...  
Keyword(s):  
Pressure Gradient ◽  
Stent Graft ◽  
Peak Pressure ◽  
Circulatory System ◽  
Valve Design ◽  
Mock Circulatory System ◽  
Valved Conduit ◽  
Valve In Valve ◽  
In Vitro Performance

Abstract OBJECTIVES Handmade trileaflet expanded polytetrafluoroethylene valved conduit developed using the flip-over method has been tailored for pulmonary valve reconstruction with satisfactory outcomes. We investigated the in vitro performance of the valve design in a mock circulatory system with various conduit sizes. In our study, the design was transformed into a transcatheter stent graft system which could fit in original valved conduits in a valve-in-valve fashion. METHODS Five different sizes of valved polytetrafluoroethylene vascular grafts (16, 18, 20, 22 and 24 mm) were mounted onto a mock circulatory system with a prism window for direct leaflets motion observation. Transvalvular pressure gradients were recorded using pressure transducers. Mean and instant flows were determined via a rotameter and a flowmeter. Similar flip-over trileaflet valve design was then carried out in 3 available stent graft sizes (23, 26 and 28.5 mm, Gore aortic extender), which were deployed inside the valved conduits. RESULTS Peak pressure gradient across 5 different sized graft valves, in their appropriate flow setting (2.0, 2.5 and 5.0 l/min), ranged from 4.7 to 13.2 mmHg. No significant valve regurgitation was noted (regurgitant fraction: 1.6–4.9%) in all valve sizes and combinations. Three sizes of the trileaflet-valved stent grafts were implanted in the 4 sizes of valved conduits except for the 16-mm conduit. Peak pressure gradient increase after valved-stent graft-in-valved-conduit setting was <10 mmHg in all 4 conduits. CONCLUSIONS The study showed excellent in vitro performance of trileaflet polytetrafluoroethylene valved conduits. Its valved stent graft transformation provided data which may serve as a reference for transcatheter valve-in-valve research in the future.

scholarly journals CRT-800.12 Effect Of Transcatheter Aortic Valve Size And Position On Valve-in-valve Hemodynamics: An In-vitro Study

2017 ◽  
Vol 10 (3) ◽  
pp. S66
Author(s):  
Matheus Simonato ◽  
Ali Azadani ◽  
Michael Reardon ◽  
Gabriel Aldea ◽  
Georg Nickenig ◽  
...  
Keyword(s):  
Aortic Valve ◽  
In Vitro Study ◽  
Vitro Study ◽  
Transcatheter Aortic Valve ◽  
Valve Size ◽  
Valve In Valve

Effect of size and position of self-expanding transcatheter valve on haemodynamics following valve-in-valve procedure in small surgical bioprostheses: an in vitro study

2018 ◽  
Vol 14 (3) ◽  
pp. e282-e289 ◽  
Author(s):  
Anne-Sophie Zenses ◽  
Morgane A. Evin ◽  
Viktória Stanová ◽  
Marie-Annick Clavel ◽  
Paul Barragan ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
Valve In Valve ◽  
Transcatheter Valve

scholarly journals In vitro study of a biological prosthetic valve for seamless fixation

2018 ◽  
Vol 19 (4) ◽  
pp. 61-69
Author(s):  
K. U. Klyshnikov ◽  
E. A. Ovcharenko ◽  
A. N. Stasev ◽  
N. A. Scheglova ◽  
Yu. N. Odarenko ◽  
...  
Keyword(s):  
Prosthetic Valve ◽  
In Vitro Study ◽  
Cardiac Valve ◽  
Breaking Force ◽  
Heart Model ◽  
Bovine Heart ◽  
Combined Operation ◽  
Valve In Valve

Aim: to evaluate the manipulative properties of the system being developed for cardiac valve re-operation on an in vitro bovine heart model.Material and methods. The prototype of the prosthesis being developed, mounted on the implant holder, as well as the dilatation balloon of its own design, were used as the objects of the study. The bioprosthesis «UniLine» of 21 mm size for the aortic position was chosen as the target site of implantation, which was established by the «classical» suture method. After that, the implantation of the tested device was carried out as a «valve in valve» and the quality of the installation and the combined operation of all the components of the re-prosthesis system were evaluated.Results. The test implantation demonstrated the consistency of the proposed method on the basis of balloon seamless fi xation, as well as high ergonomic characteristics: the average time of seamless implantation of the developed prototype on an in vitro animal heart model was 3 minutes versus the implantation of the «UniLine» bioprosthesis – 11 min, Implantation provided a reliable prosthesis The breaking force was 12.9 N, which is equivalent to a pressure of 279 mm Hg. 

scholarly journals Factors Affecting Lethal Isotherms During Cryoablation Procedures

2016 ◽  
Vol 10 (1) ◽  
pp. 62-71 ◽  
Author(s):  
Andrew C. Rau ◽  
Ryan Siskey ◽  
Jorge A. Ochoa ◽  
Tracy Good
Keyword(s):  
Cell Death ◽  
Renal Tumors ◽  
Probe Type ◽  
Operating Pressure ◽  
Factors Affecting ◽  
Clinical Method ◽  
Probe Size ◽  
Type Size ◽  
Target Treatment

Background: Creating appropriately-sized, lethal isotherms during cryoablation of renal tumors is critical in order to achieve sufficiently-sized zones of cell death. To ensure adequate cell death in target treatment locations, surgeons must carefully select the type, size, location, and number of probes to be used, as well as various probe operating parameters. Objective: The current study investigates the effects of probe type, operating pressure, and clinical method on the resulting sizes of isotherms in an in vitro gelatin model. Method: Using a total of four cryoprobes from two manufacturers, freeze procedures were conducted in gelatin in order to compare resulting sizes of constant temperature zones (isotherms). The effects of certain procedural parameters which are clinically adjustable were studied. Results: Test results show that the sizes of 0 °C,-20 °C and -40 °C isotherms created by similarly-sized probes from two different manufacturers were significantly different for nearly all comparisons made, and that size differences resulting from changing the operating pressure were not as prevalent. Furthermore, isotherm sizes created using a multiple freeze procedure (a ten minute freeze, followed by a five minute passive thaw, followed by another ten minute freeze) did not result in statistically-significant differences when compared to those created using a single freeze procedure in all cases. Conclusion: These results indicate that selection of the probe manufacturer and probe size may be more important for dictating the size of kill zones during cryoablation than procedural adjustments to operating pressures or freeze times.

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