title: Effect of cannula shape on aortic wall and flow turbulence: hydrodynamic study during extracorporeal circulation in mock thoracic aorta.
abstract: This study was designed to analyze flow pattern, velocity, and strain on the aortic wall of a glass aortic model during extracorporeal circulation, and to elucidate the characteristics of flow pattern in four aortic cannulas. Different patterns of large vortices and helical flow were made by each cannula. The high-velocity flow (0.6 m/s) was observed in end-hole cannula, causing high strain rate tensor (0.3~0.4 without unit) on the aortic arch. In dispersion cannula, a decreased strain rate tensor (less than 0.1) was found on the outer curvature of the aortic arch. In Soft-flow cannula (3M Cardiovascular, Ann Arbor, MI, USA), further decreased flow velocity (0.2 m/s) and strain (less than 0.2) were observed. In Select 3D cannula (Medtronic, Inc., Minneapolis, MN, USA), a high strain (0.4~0.5) was observed along the inner curvature of the aortic arch. In conclusion, end-hole cannula should not be used in atherosclerotic aorta. Particular attention should be paid both for selection of cannulas and cannulation site based on this result.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Hirosaki University School of Medicine, Hirosaki, Japan.
authors.forename: Masahito
authors.initials: M
authors.lastname: Minakawa
authors.forename: Ikuo
authors.initials: I
authors.lastname: Fukuda
authors.forename: Junichi
authors.initials: J
authors.lastname: Yamazaki
authors.forename: Kozo
authors.initials: K
authors.lastname: Fukui
authors.forename: Hideki
authors.initials: H
authors.lastname: Yanaoka
authors.forename: Takao
authors.initials: T
authors.lastname: Inamura
mesh_terms: D001013:Aorta, Thoracic / Q000502:physiology*; D001696:Biomechanical Phenomena; D002404:Catheterization / Q000295:instrumentation*; D005112:Extracorporeal Circulation; D006801:Humans; D008955:Models, Cardiovascular; D010477:Perfusion / Q000295:instrumentation; D012212:Rheology