One common but not well-understood phenomenon of temporary mechanical circulatory support (MCS) use is thrombocytopenia. This clinical issue increases the risk of bleeding and the need for platelet transfusion. Addition-ally, heparin-induced thrombocytopenia must be considered as part of the differential diagnosis, which complicates patient management. In what follows, we analyze the degree and relative rate of platelet count drop with various temporary MCS strategies - Impella 5.5; Veno-venous Extracorporeal Membrane Oxygenation (VV ECMO); Veno-arterial ECMO (VA ECMO); Intra-aortic Balloon Pump (IABP) and Centrimag Biventricular Assist Device (BIVAD). A total of 337 cohort was investigated. 77 was included for analysis after strict exclusion criteria were utilized (plate-let transfusions, bleeding complications, etc.). Repeated measure mixed effect and linear regression models were used to assess the percent platelet drop on implantation of MCS and recovery after explantation of MCS. A statisti-cally significant mean percent drop occurred in MCS types - VA ECMO(-69.6%, p < 0.001), VV ECMO(-40.9%, p < 0.001), Impella 5.5(-20.9%, p = 0.01) and IABP(-28.3%, p = 0.01), except Centrimag BIVAD(-6.5%, p = 0.61). Platelet recovery to or above baseline occurred in VA ECMO(+107.0%, p = 0.42), Impella 5.5(+117.2%, p = 0.28), IABP(+108.3%, p = 0.37), VV-ECMO(163.3%, p = 0.01*) and Centrimag BIVAD(+100.1%, p = 0.99). These re-sults show that the degree of thrombocytopenia depends on MCS device type and is reversible.(c) 2022 Published by Elsevier Inc.