The Unique Impact of Blood Type O on Gastrointestinal Bleeding with Left Ventricular Assist Systems

Purpose Acquired von Willebrand syndrome is implicated in the pathology of gastrointestinal bleeding (GIB) after implantation of continuous-flow left ventricular assist systems (CF-LVAS). Adults with blood type (BT) O have lower circulating levels of von Willebrand factor. In this analysis, we sought to explore the association between BT O and GIB following CF-LVAS implantation. Methods We performed a single center, retrospective, observational cohort study in 200 consecutive adults implanted with a durable CF-LVAS over a 10-year period (2008-2018). Patients were grouped according to BT O (N = 97) vs Non-O (N = 103), and further stratified by the HAS-BLED score. Cumulative Kaplan-Meier event curves were constructed. Results Patients with at least 1 GIB event were generally older (60.8±10.1 vs 53.0±13.9 years, P ;=3 (N = 87) the rates of GIB were significantly higher for BT O (HR, 2.36; 95% CI, 1.06-5.27; P = 0.036) (Figure). Conclusion Our study suggests an important association of BT O with higher rates of GIB in CF-LVAS patients at high baseline risk for bleeding complications (HAS-BLED >;=3). These findings suggest that in this specific population characterized by BT O, a greater vigilance and targeted anticoagulation strategies may need to be investigated.