Load Sensitivity of Rotary Blood Pumps under Static Pressure Conditions

Static-pressure head−flow characteristics were studied for six models of rotary blood pumps: Incor (BerlinHeart, Germany), HeartMate II (Thoratec Corp., USA), Sputnik and Sputnik 2 (JSC ZITC, Russia), Heartware HVAD (Heartware International, Inc., USA), and Duraheart (Terumo, Japan). Preload and afterload sensitivities were calculated for each pump model. Preload sensitivity was found to decrease in the maximum blood flow area. It was shown that preload sensitivity depends on the geometry of the pump rotor bundle rather than the type of the pump (centrifugal or axial-flow).