P65: Predictors of Bleeding with Rotational Thromboelastometry in Patients with a Left Ventricular Assist Device

Abstract

Purpose: Bleeding events are a significant source of morbidity and mortality in patients with left ventricular assist devices (LVAD). Rotational thromboelastometry (ROTEM) is a form of viscoelastographic testing that provides a real-time analysis of clot initiation, clot strength, and fibrinolysis. There is limited data regarding the use of ROTEM in predicting bleeding events in patients with LVADs post-implantation. Therefore, the purpose of this study is to determine if any component in ROTEM is associated with bleeding events in LVAD patients. Methods: This was a retrospective, single-centered, cohort study of LVAD patients implanted between January 2013 to December 2022 that compared ROTEM values between patients admitted due to bleeding and non-bleeding controls. ROTEM values drawn within 24 hours of separate hospitalizations were included. Patient encounters were excluded for the following reasons: ROTEM drawn after receiving blood or anticoagulant reversal agent, parenteral anticoagulation, or direct oral anticoagulants, and admission related to thrombotic events, index implantation, or device exchange. The primary outcome was to determine if ROTEM values were associated with bleeding events. Results: Of the 327 patient admissions evaluated, 266 patient encounters met inclusion criteria with 59 (22.2%) bleeding events and 207 (77.2%) controls. Of the excluded patients, 28 patients were excluded due to ROTEM drawn after receiving blood or an anticoagulant reversal agent. Baseline characteristics including age, gender, race, ethnicity, device type, last ejection fraction, and indication for implant were similar between groups. Patients admitted for a bleeding event were more likely to have a history of any bleeding event (p=0.01). There was no significant difference seen in the regression analysis evaluating INTEM clot time (p=0.55), INTEM clotting formation time (p=0.45), EXTEM clotting time (p=0.72), FIBTEM clot formation time (p=0.78), and FIBTEM clotting time (p=0.78) for patients experiencing a bleeding event vs those without a bleeding event (table 1). Conclusion: There are no differences in ROTEM values in LVAD patients admitted for bleeding events compared to non-bleeding admissions. Table 1.