The use of arterial line filters has long been a standard of practice in the field of cardiopulmonary bypass. Sorin Biomedica has designed an adult hollow-fiber oxygenator that not only incorporates their Mimesys biomimicry coating technology but also has a 40-micron arterial filter as an integrated component of this unique membrane oxygenator. We did a prospective, randomized clinical trial of 54 Synthesis coated oxygenators and compared them with 54 uncoated Monolyth Pro oxygenators, the latter of which incorporated an external arterial line filter with a standard bypass loop There were few statistically significant differences found between the Synthesis group and the Monolyth group with regard to pressure differentials, hemodynamic resistance, and platelet drop. The Synthesis oxygenator did require less priming volume, but the amount was not significant. Platelet counts with the Phosphorylcholine coated Synthesis oxygenators, using crystalloid perfusates, was similar to our previously published data on platelet protection and Albumin perfusates. We conclude that the Sorin Synthesis oxygenator appears to have better flow characteristics than the Monolyth oxygenator, with the potential for lower priming volumes. The most clinically significant benefit comes from the elimination of the arterial filter bypass loop and the avoidance of inverting the arterial filter during priming.