© The Author(s) 2022.Background: Minimally invasive extracorporeal circulation (MiECC) is employed as a strategy to attenuate the physiologic disturbance caused by cardiopulmonary bypass. The aim of this study was to compare the coagulation profile of MiECC to an optimized conventional extracorporeal circuit (OpECC) with regards to platelet function, rotational thromboelastometry and blood product usage. Methods: A retrospective analysis of coronary artery bypass grafting operations using either MiECC or OpECC was performed at a single institution. Results: A total of 112 patients were included, with 61 receiving MiECC and 51 OpECC patients. OpECC patients had a significantly larger BSA (1.95+/- 0.22m2 vs 1.88 +/- 0.18m2, p = 0.034), than those who received MiECC. No difference between groups was observed regarding red blood cell, plasma, and platelet transfusions. Functional platelet count during the warming phase of cardiopulmonary bypass was found to be higher in the MiECC group ((136 (102–171) x109/L vs 109 (94–136) x109/L), p = 0.027), as were functional platelets as a percent of total platelet count ((86 (77–91)% vs 76 (63–82)%), p = 0.003). There were no significant differences between other outcomes such as operative mortality, incidence of stroke, and intensive care unit length of stay. Conclusion: While we did not see a difference in blood transfusions, MiECC resulted in a statistically significant advantage over OpECC with regards to preservation of functional platelets.