Hemostatic Disorder During Left Ventricular Assist Device Implantation in Swine

Introduction: Implantation of left ventricular assist devices (LVAD) conventionally requires the use of cardiopulmonary bypass (CPB). Among others, mechanical circulatory support devices favor intraoperative hemostatic disorder. Hypothesis: Despite the high risk of severe bleeding and thromboembolic complications, little is known about the intraoperative extent of hemostatic disorder during LVAD implantation.This study aimed to determine the extent of hemostatic disorder during LVAD implantation in a porcine model under CPB and LVAD support, separately. Methods: We performed LVAD implantation in 10 female German Landrace pigs (body weight 104 ± 13 kg). Blood samples were collected three times: at (1) Baseline, (2) after CPB and (3) after LVAD. For CPB, cannulation of the left jugular vein and right femoral artery was performed. After sternotomy and pericardiotomy, apical coring was performed under CPB. A continuous-flow LVAD with transventricular outflow graft was implanted. For CPB and LVAD, a flow rate of 3-7 L/min and a rotational speed of 4000 to 7200 rpm were aimed, respectively. Hemostatic laboratory markers from all times were compared by Wilcoxon signed rank test. Results: Compared to Baseline, CPB led to a significant decrease of fibrinogen and antithrombin as well as an increase of von Willebrand factor (vWF) ratio and D dimer (DD). Compared to after CPB, there was a continued decrease of antithrombin and an increase of DD, as well as a significant increase of vWF and vWF activity under LVAD support. Conclusion: Among others, CPB and LVAD separately contribute to hemostatic disorder during LVAD implantation. Human laboratory markers allowed early detection of intraoperative hemostatic changes in pigs. Further studies are needed to investigate whether off-pump LVAD implantation reduces perioperative hemostatic disorder.