title: The 12 cc Penn State pulsatile pediatric ventricular assist device: fluid dynamics associated with valve selection.
abstract: The mortality rate for infants awaiting a heart transplant is 40% because of the extremely limited number of donor organs. Ventricular assist devices (VADs), a common bridge-to-transplant solution in adults, are becoming a viable option for pediatric patients. A major obstacle faced by VAD designers is thromboembolism. Previous studies have shown that the interrelated flow characteristics necessary for the prevention of thrombosis in a pulsatile VAD are a strong inlet jet, a late diastolic recirculating flow, and a wall shear rate greater than 500 s(-1). Particle image velocimetry was used to compare the flow fields in the chamber of the 12 cc Penn State pediatric pulsatile VAD using two mechanical heart valves: Bjork-Shiley monostrut (BSM) tilting disk valves and CarboMedics (CM) bileaflet valves. In conjunction with the flow evaluation, wall shear data were calculated and analyzed to help quantify wall washing. The major orifice inlet jet of the device containing BSM valves was more intense, which led to better recirculation and wall washing than the three jets produced by the CM valves. Regurgitation through the CM valve served as a significant hindrance to the development of the rotational flow.
authors.affiliation: Department of Bioengineering, The Pennsylvania State University, 205 Hallowell Building, University Park, PA 16802, USA.
authors.forename: Benjamin T
authors.initials: BT
authors.lastname: Cooper
authors.forename: Breigh N
authors.initials: BN
authors.lastname: Roszelle
authors.forename: Tobias C
authors.initials: TC
authors.lastname: Long
authors.forename: Steven
authors.initials: S
authors.lastname: Deutsch
authors.forename: Keefe B
authors.initials: KB
authors.lastname: Manning
mesh_terms: D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D003198:Computer Simulation; D017076:Computer-Aided Design; D019544:Equipment Failure Analysis / Q000379:methods*; D006353:Heart-Assist Devices; D006801:Humans; D008955:Models, Cardiovascular; D011474:Prosthesis Design / Q000379:methods; D011673:Pulsatile Flow / Q000502:physiology*; D012212:Rheology / Q000379:methods; D016276:Ventricular Function