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1.
JTCVS Open ; 9: 59-69, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36003435

RESUMEN

Background: This study assessed the long-term hemodynamic functional performance of the new Inspiris Resilia aortic valve after accelerated wear testing (AWT). Methods: Three 21-mm and 23-mm Inspiris valves were used for the AWT procedure. After 1 billion cycles (equivalent to 25 years), the valves' hemodynamic performance was compared with that of the corresponding zero-cycled condition. Next, 1 AWT cycled valve of each valve size was selected at random for particle image velocimetry (PIV) and leaflet kinematic tests, and the data were compared with data for an uncycled Inspiris Resilia aortic valve of the same size. PIV was used to quantitatively evaluate flow fields downstream of the valve. Valves were tested according to International Standards Organization 5840-2:2015 protocols. Results: The 21-mm and 23-mm valves met the International Organization for Standardization (ISO) durability performance requirements to 1 billion cycles. The mean effective orifice areas for the 21-mm and 23-mm zero-cycled and 1 billion-cycled valves were 1.89 ± 0.02 cm2 and 1.94 ± 0.01 cm2, respectively (P < .05) and 2.3 ± 0.13 cm2 and 2.40 ± 0.11 cm2, respectively (P < .05). Flow characterization of the control valves and the study valves demonstrated similar flow characteristics. The velocity and shear stress fields were also similar in the control and study valves. Conclusions: The Inspiris Resilia aortic valve demonstrated very good durability and hemodynamic performance after an equivalent of 25 years of simulated in vitro accelerated wear. The study valves exceeded 1 billion cycles of simulated wear, 5 times longer than the standard requirement for a tissue valve as stipulated in ISO 5840-2:2015.

2.
JACC Basic Transl Sci ; 5(8): 755-766, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32875167

RESUMEN

Valvular heart diseases are associated with significant cardiovascular morbidity and mortality, and often require surgical and/or percutaneous repair or replacement. Valve replacement is limited to mechanical and biological prostheses, the latter of which circumvent the need for lifelong anticoagulation but are subject to structural valve degeneration (SVD) and failure. Although calcification is heavily studied, noncalcific SVD, which represent roughly 30% of BHV failures, is relatively underinvestigated. This original work establishes 2 novel and interacting mechanisms-glycation and serum albumin incorporation-that occur in clinical valves and are sufficient to induce hallmarks of structural degeneration as well as functional deterioration.

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