Hemocompatibility of the Realheart TAH against SynCardia TAH in full-body circulation with human blood

Abstract The SynCardia Total Artificial Heart (TAH) is FDA-approved for bridge to transplantation and has been implanted in > 2,100 patients. Clinical data demonstrate hemolysis whilst preserving von Willebrand factor (VWF), but no published in vitro blood damage profile exists. Such baseline data are important for developing and evaluating next-generation TAH systems. The Realheart TAH is a four-chamber pulsatile positive displacement TAH which mimics the natural heart’s atrioventricular plane movement for physiological flow patterns and gentle blood handling. This study compares the hemocompatibility of SynCardia and Realheart in a full-body circulation test setup. Hemolysis testing of pooled human blood was performed according to ASTM standards in a mock loop simulating systemic and pulmonary circulation. Complete blood counts were obtained using automated hematology analysis. Plasma samples were assessed for VWF activity and antigen by ELISA. Mean mgNIH ( n = 6) was 226.0 ± 30.6 mg/100 L for SynCardia and 35.5 ± 4.3 mg/100 L for Realheart ( p = 0.002), a 6.36-fold increase in SynCardia. MIH values were 20.80 ± 2.65 and 3.27 ± 0.37, respectively ( p = 0.002). SynCardia significantly increased cell-derived fragments compared to Realheart, whilst both devices preserved VWF. Realheart demonstrated substantially improved hemocompatibility under matched full-body circulation conditions.