Clinical and Hemodynamic Efficacy of Left Ventricular Unloading during Venoarterial Extracorporeal Membrane Oxygenation

Purpose Left ventricular (LV) distention is a feared complication in patients on venoarterial extracorporeal membrane oxygenation (VA-ECMO) for cardiogenic shock. LV unloading could be achieved with concomitant intra-aortic balloon pump (IABP) or Impella. We sought to assess the clinical and hemodynamic effects of IABP and Impella on patients supported with VA-ECMO Methods We conducted a retrospective review of patients who received VA-ECMO at our institution between January 2015 and June 2020. Patients with post-cardiotomy shock were excluded. Patients were categorized as having received either ECMO alone or ECMO+LV unloading. LV unloading was further characterized as either ECMO+IABP, or ECMO+Impella. We recorded baseline characteristics, post-operative complications, and hemodynamic changes associated with device initiation. Results During the study period, 142 patients received ECMO alone, 76 received ECMO+IABP, and 76 received ECMO+Impella. The ECMO+LV unloading group had more male patients compared to ECMO alone (70.4% vs 57.5%, p=0.026). 39.4% of ECMO alone patients survived to discharge, compared to 44.4% of ECMO+LV unloading patients (p=0.12). The ECMO+LV unloading group showed a greater decrease in mean pulmonary diastolic pressures compared to ECMO alone after 24 hours of support (-6.0 ± 8.4 mmHg vs -0.1 ± 10.8 mmHg, p = 0.032). ECMO+Impella patients had a higher incidence of bleeding events compared to ECMO alone or ECMO+IABP (52.6% vs 37.3% vs 20.8%, p = 0.0003). Kaplan Meier analysis revealed that ECMO+IABP had better survival compared to ECMO alone and ECMO+Impella (Figure 1). In a multivariable Cox-hazard analysis, age (HR= 1.02), male sex (HR=0.57), baseline lactate (HR =1.05), baseline creatinine (HR=1.06), need for ECPR (HR=2.21) and presence of IABP (HR=0.48) were independent predictors for mortality. Conclusion Concomitant support with IABP may help to reduce morbidity in patients on VA-ECMO for cardiogenic shock.