title: Hydrodynamic evaluation of a new dispersive aortic cannula (Stealthflow).
abstract: The aim of this study was to evaluate flow from a new dispersive aortic cannula (Stealthflow) in the aortic arch using flow visualization methods. Particle image velocimetry was used to analyze flow dynamics in the mock aortic model. Flow patterns, velocity distribution, and streamlines with different shape cannulas were evaluated in a glass aortic arch model. We compared flow parameters in two different dispersive type cannulas: the Stealthflow and the Soft-flow cannula. A large vortex and regurgitant flow were observed in the aortic arch with both cannulas. With the Stealthflow cannula, a high-velocity area with a maximum velocity of 0.68 m/s appeared on the ostium of the cannula in the longitudinal plane. With the Soft-flow cannula, 'multiple jet streams, each with a velocity less than 0.60 m/s, were observed at the cannula outlet. Regurgitant flow from the cannula to the brachiocephalic artery and to the ascending aorta on the greater curvature was specific to the Soft-flow cannula. The degree of regurgitation on the same site was lower with the Stealthflow cannula than with the Soft-flow cannula. The Stealthflow cannula has similar flow properties to those of the Soft-flow cannula according to glass aortic model analysis. It generates gentle flow in the aortic arch and slow flow around the ostia of the aortic arch vessels. The Stealthflow cannula is as effective as the Soft-flow cannula. Care must be taken when the patient has thick atheromatous plaque or frail atheroma on the lesser curvature of the aortic arch.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Japan. me-goto@hirosaki-u.ac.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Goto
authors.affiliation: Department of Intelligent Machines and System Engineering, Faculty of Science and Technology, Hirosaki University, Hirosaki, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Inamura
authors.affiliation: Physics of Fluids Group, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands.
authors.forename: Minori
authors.initials: M
authors.lastname: Shirota
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Wakako
authors.initials: W
authors.lastname: Fukuda
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Ikuo
authors.initials: I
authors.lastname: Fukuda
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Daitoku
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Masahito
authors.initials: M
authors.lastname: Minakawa
authors.affiliation: Department of Cardiovascular Surgery, Aomori Municipal Hospital, Aomori, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Ito
mesh_terms: D001011:Aorta; D001013:Aorta, Thoracic / Q000502:physiology*; D001783:Blood Flow Velocity; D016122:Brachiocephalic Trunk; D000072601:Cannula; D017700:Embolism, Cholesterol / Q000517:prevention & control; D006801:Humans; D057446:Hydrodynamics; D008955:Models, Cardiovascular; D012212:Rheology
keywords: Aortic perfusion; Extracorporeal circulation; Sandblast effect; Shear stress