title: The Effect of Geometry on the Efficiency and Hemolysis of Centrifugal Implantable Blood Pumps.
abstract: The application of centrifugal pumps as heart assist devices imposes design limitations on the impeller geometry. Geometry and operating parameters will affect the performance and the hemocompatibility of the device. Among all the parameters affecting the hemocompatibility, pressure, rotational speed, blade numbers, angle, and width have significant impact on the blood trauma. These parameters directly (pressure, speed) and indirectly (geometry) affect the efficiency of the pump as well. This study describes the experimental investigation on geometric parameters and their effect on the performance of small centrifugal pumps suitable for Mechanical Circulatory Support (MCS) devices. Experimental and numerical techniques were implemented to analyze the performance of 15 centrifugal impellers with different characteristics. The effect of each parameter on the pump performance and hemolysis was studied by calculating the normalized index of hemolysis (NIH) and the shear stress induced in each pump. The results show five and six blades, 15-35° outlet angle, and the lowest outlet width that meets the required pressure rise are optimum values for an efficient hemocompatible pump.
authors.affiliation: From the *School of Engineering and Materials Science, Queen Mary University of London, London, United Kingdom; †Department of Cardiology. Barts and the London NHS Trust, London Chest Hospital, London, United Kingdom; and ‡Parks College of Engineering, Aviation and Technology, Saint Louis University, St. Louis, Missouri.
authors.forename: Sahand
authors.initials: S
authors.lastname: Mozafari
authors.forename: Mohammad A
authors.initials: MA
authors.lastname: Rezaienia
authors.forename: Gordon M
authors.initials: GM
authors.lastname: Paul
authors.forename: Martin T
authors.initials: MT
authors.lastname: Rothman
authors.forename: Pihua
authors.initials: P
authors.lastname: Wen
authors.forename: Theodosios
authors.initials: T
authors.lastname: Korakianitis
mesh_terms: D002498:Centrifugation; D004867:Equipment Design; D006353:Heart-Assist Devices; D006461:Hemolysis; D006801:Humans; D013314:Stress, Mechanical