Blood Trauma Testing of CentriMag and RotaFlow Centrifugal Flow Devices: A Pilot Study Michael A. Sobieski, Guruprasad A. Giridharan, Mickey Ising, Steven C. Koenig, and Mark S. Slaughter Departments of Bioengineering & Surgery, Cardiovascular Innovation Institute, University of Louisville, Louisville, KY, USA Abstract: Mechanical circulatory assist devices that provide temporary support in heart failure patients are needed to enable recovery or provide a bridge to decision. Minimizing risk of blood damage (i.e., hemolysis) with these devices is critical, especially if the length of support needs to be extended. Hematologic responses of the Rota- Flow (Maquet) and CentriMag (Thoratec) temporary support devices were characterized in an in vitro feasibility study. Paired static mock flow loops primed with fresh bovine blood (700 mL, hematocrit [Hct] = 25  3%, heparin titrated for activated clotting time >300 s) pooled from a single-source donor were used to test hematologic responses to RotaFlow (n = 2) and CentriMag (n = 2) simultaneously. Pump differential pressures, temperature, and flow were maintained at 250  10 mm Hg, 25  2°C, and 4.2  0.25 L/min, respectively. Blood samples (3 mL) were collected at 0, 60, 120, 180, 240, 300, and 360 min after starting pumps in accordance with recommended Food and Drug Administration and American Society for Testing and Materials guidelines. The CentriMag operated at a higher average pump speed (3425 rpm) than the RotaFlow (3000 rpm) while maintaining similar constant flow rates (4.2 L/min). Hematologic indicators of blood trauma (hemoglobin, Hct, platelet count, plasma free hemoglobin, and white blood cell) for all measured time points as well as normalized and modified indices of hemolysis were similar (RotaFlow: normalized index of hemolysis [NIH] = 0.021  0.003 g/100 L, modified index of hemolysis [MIH] = 3.28  0.52 mg/mg compared to CentriMag: NIH = 0.041  0.010 g/100 L, MIH = 6.08  1.45 mg/mg). In this feasibility study, the blood trauma performance of the RotaFlow was similar or better than the CentriMag device under clinically equivalent, worst-case test conditions. The RotaFlow device may be a more cost-effective alternative to the CentriMag. Key Words: Hemolysis testing— Blood trauma—Mechanical circulatory support—Tempor- ary support. Temporary placement of continuous-flow, mecha- nical circulatory support devices (MCSDs) has become standard therapy for providing perioperative or postcardiotomy circulatory support in heart failure patients (1–3). Short-term support with rotary blood pumps may be extended by a few days to enable clinicians time to evaluate the patients’ potential for recovery or as a bridge to decision (4).The CentriMag ventricular assist system is currently undergoing clinical trials in the USA for short-term support in patients with cardiac dysfunction who fail to wean from cardiopulmonary bypass. Concerns exist that the high operational speeds associated with these tempo- rary rotary blood pumps may cause hemolysis due to blood trauma caused by turbulent flow, high shear stresses, and surface interactions (5,6). Subsequently, risk of hemolysis may increase if temporary MCSD duration is extended for a few days. Additionally, a variety of temporary blood pumps that have distinct design characteristics may also affect hematologic responses. Minimizing blood trauma is a fundamental requirement for all blood pumps.The Food and Drug doi:10.1111/j.1525-1594.2012.01514.x Received February 2012; revised June 2012. Address correspondence and reprint requests to Prof. Mark S. Slaughter, Professor and Chief, Division of Thoracic and Cardio- vascular Surgery, Cardiovascular Innovation Institute, Rm 411, 302 East Muhammad Ali Blvd, University of Louisville, Louisville, KY 40202, USA. E-mail: mark.slaughter@louisville.edu Presented in part at the 19th Congress of the International Society for Rotary Blood Pumps, held on September 8–10, 2011, in Louisville, KY, USA. © 2012, Copyright the Authors Artificial Organs © 2012, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc. Artificial Organs 2012, 36(8):677–682