Paper Info
Title
Mechanical heart valve cavitation in patients with bileaflet valves.
Abstract
Today, the quality of mechanical heart valves is quite high, and implantation has become a routine clinical procedure with a low operative mortality (< 5%). However, patients still face the risks of blood cell damage, thromboembolic events, and material failure of the prosthetic device. One mechanism found to be a possible contributor to these adverse effects is cavitation. In vitro, cavitation has been directly demonstrated by visualization and indirectly in vivo by registering of high frequency pressure fluctuations (HFPF). Tilting disc valves are thought of having higher cavitation potential than bileaflet valves due to higher closing velocities. However, the thromboembolic potential seems to be the same. Further studies are therefore needed to investigate the cavitation potential of bileaflet valves in vivo. The post processing of HFPF have shown difficulties when applied on bileaflet vavles due to asynchronous closure of the two leaflets. The aim of this study was therefore to isolate the pressure signature from each leaflet closure and perform cavitation analyses on each component. Six patients were included in the study (St. Jude Medical (n=3) and CarboMedics (n=3); all aortic bileaflet mechanical heart valves). HFPFs were recorded intraoperatively through a hydrophone at the aortic root. The pressure signature relating to the first and second leaflet closure was isolated and cavitation parameters were calculated (RMS after 50 kHz highpass filtering and signal energy). Data were averaged over 30 heart cycles. For all patients both the RMS value and signal energy of the second leaflet closure were higher than for the first leaflet closure. This indicates that the second leaflet closure is most prone to cause cavitation. Therefore, quantifying cavitation based on the HFPF related to the second leaflet closure may suggest that the cavitation potential for bileaflet valves in vivo may be higher than previous studies have suggested.
Year
DOI
Venue
2014
10.1109/EMBC.2014.6944910
EMBC
Keywords
Field
DocType
tilting disc valves,cellular biophysics,artificial organs,blood cell damage,hydrophone,material failure,high frequency pressure fluctuations,thromboembolic events,bileaflet valves,aortic root,prosthetic device,operative mortality,hydrophones,mechanical heart valve cavitation,blood
Internal medicine,Cardiology,Engineering,Mechanical heart-valve,Cavitation
Conference
Volume
ISSN
Citations 
2014
1557-170X
0
PageRank 
References 
Authors
0.34
0
5
Name
Order
Citations
PageRank
Peter Johansen121.78
Tina S Andersen200.34
J Michael Hasenkam300.34
Hans Nygaard400.68
Peter K Paulsen500.34