We have located links that may give you full text access.
Journal Article
Research Support, U.S. Gov't, P.H.S.
Mechanisms of cavitation and the formation of stable bubbles on the Björk-Shiley Monostrut prosthetic heart valve.
Journal of Heart Valve Disease 2002 January
BACKGROUND AND AIMS OF THE STUDY: Transcranial Doppler studies performed on patients with the Björk-Shiley Monostrut mechanical heart valve have detected signals typical of gaseous emboli.
METHODS: In this study, a high-speed digital imaging system was used to examine the closure event of the Björk-Shiley Monostrut valve in vitro.
RESULTS: Observations support the hypothesis that cavitation occurs before the formation of stable gas bubbles. Bubble cavitation occurs at the instant of valve closure and lasts on the order of 0.3 ms. The rebounding motion of the occluder initiates the development of a vortex which induces vortex cavitation. Vortex cavitation begins approximately 0.5 ms after impact of the occluder and the valve housing (approximately 0.2 ms after bubble cavitation has subsided), and lasts for approximately 1 ms. The formation of stable bubbles occurs later, along the center of the vortex that persists throughout much of the first rebound.
CONCLUSION: It is hypothesized that the low-pressure region at the center of the vortex contributes to the formation of stable bubbles by collecting expanded nuclei that arise from both bubble and vortex cavitation, and providing a low-pressure environment in which the nuclei combine and continue to grow.
METHODS: In this study, a high-speed digital imaging system was used to examine the closure event of the Björk-Shiley Monostrut valve in vitro.
RESULTS: Observations support the hypothesis that cavitation occurs before the formation of stable gas bubbles. Bubble cavitation occurs at the instant of valve closure and lasts on the order of 0.3 ms. The rebounding motion of the occluder initiates the development of a vortex which induces vortex cavitation. Vortex cavitation begins approximately 0.5 ms after impact of the occluder and the valve housing (approximately 0.2 ms after bubble cavitation has subsided), and lasts for approximately 1 ms. The formation of stable bubbles occurs later, along the center of the vortex that persists throughout much of the first rebound.
CONCLUSION: It is hypothesized that the low-pressure region at the center of the vortex contributes to the formation of stable bubbles by collecting expanded nuclei that arise from both bubble and vortex cavitation, and providing a low-pressure environment in which the nuclei combine and continue to grow.
Full text links
Related Resources
Trending Papers
Interstitial Lung Disease: A Review.JAMA 2024 April 23
Review article: Recent advances in ascites and acute kidney injury management in cirrhosis.Alimentary Pharmacology & Therapeutics 2024 March 26
Executive Summary: State-of-the-Art Review: Unintended Consequences: Risk of Opportunistic Infections Associated with Long-term Glucocorticoid Therapies in Adults.Clinical Infectious Diseases 2024 April 11
Clinical practice guidelines on the management of status epilepticus in adults: A systematic review.Epilepsia 2024 April 13
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app