Abstract 4138583: Incidence and Outcomes of Heparin-Induced Thrombocytopenia Among Patients Undergoing Left Ventricular Assist Device Implantation

Background: Left Ventricular Assist Devices (LVAD) are being increasingly used as a bridge to transplant and destination therapy for advanced (stage D) heart failure. Heparin-induced thrombocytopenia (HIT) increases the risk of thromboembolic and bleeding events. HIT is also a well-known complication in patients undergoing LVAD implantation. This study examines the incidence and impact of HIT on outcomes in LVAD implants using a nationwide database from 2016 to 2020. Methods: We queried the National Inpatient Sample database for 2016-2020 to identify all adults ≥ 18 who underwent LVAD insertion using ICD 10 codes. LVAD recipients were dichotomized into two cohorts by the presence of HIT. Our primary outcome was in-hospital mortality. Secondary outcomes included vascular complications, acute kidney injury (AKI), length of stay, and total cost. Outcomes were adjusted for demographic variables, hospital-level characteristics, and comorbidities using regression analysis. Results: A total of 19975 (95% CI: 18328 - 21622) hospitalization records for LVAD insertion were identified, out of which HIT occurred in 1.8%. There were significant differences in AKI requiring dialysis, (p < 0.03) cardiogenic shock, (p<0.01), mechanical ventilation (p<0.01), pulmonary embolism (PE) (p< 0.001) and acute deep vein thrombosis (DVT) (p< 0.001) which occurred more in HIT. In-hospital mortality was not significantly associated with HIT (adjusted odds ratio [aOR] 1.49, 95% CI :0.73-3.04, p value 0.28). Older age (aOR 1.02; 95% CI: 1.01-1.02) was associated with mortality after LVAD insertion. AKI, ischemic stroke, hemorrhagic stroke, acute coronary syndrome, arterial dissection, cardiogenic shock, and mechanical ventilation were significantly associated with in-hospital mortality. Our analysis did not show any differences in the incidence of vascular complications, stroke, intraoperative bleeding, blood transfusions and AKI between the HIT and non-HIT group. The HIT group stayed longer in the hospital 39 days (95% CI: 36- 38) vs 37 days (95% CI: 35- 44) and incurred higher total hospital cost of $1,101,638 vs. $1,245,616) although this was not statistically significant. Conclusion: Among US hospitalized patients undergoing LVAD implants, HIT was significantly associated with a higher risk of AKI requiring dialysis, PE, acute DVT, cardiogenic shock and need for mechanical ventilation. It was however not associated with a higher risk of in-hospital mortality.