Abstract 11322: Comparative Outcomes of Impella and Intra-Aortic Balloon Pump for Left Ventricular Unloading Among Patients With Cardiogenic Shock on Veno-Arterial Extracorporeal Membrane Oxygenation

Abstract

Background: Cardiogenic shock (CS) is associated with high morbidity and mortality. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used for patients with CS. Although Impella or Intra-aortic balloon pump (IABP) is frequently used for left ventricular (LV) unloading for increased afterload during VA-ECMO therapy, there are scarce comparative outcomes data for these devices. Aims: To compare short-term outcomes of Impella and IABP in patients on VA-ECMO for CS. Methods: Using the Nationwide Readmissions Database between 2016 and 2020, we analyzed outcomes of CS patients requiring VA-ECMO based on multivariable regression and propensity score methods. Results: Of 15,980 patients on VA-ECMO, IABP and Impella were used in 19.4% and 16.4% patients, respectively. The proportion of patients managed with Impella for LV unloading significantly increased from 2016 to 2020 (6.5% vs. 25.8%; P-trend<0.001). In-hospital mortality was higher in Impella group (54.8%) compared with ECMO only (50.4%) and IABP (48.4%) groups. After adjustment, LV unloading using IABP vs ECMO only was associated with lower in-hospital mortality (OR, 0.83; 95% CI, 0.70-0.98). LV unloading using Impella vs ECMO only had similar in-hospital mortality (OR, 1.09; 95% CI, 0.91-1.31) but was associated with more bleeding (OR, 1.21; 95% CI, 1.04-1.41) and more acute kidney injury (AKI) requiring hemodialysis (HD) (OR, 1.42; 95% CI, 1.13-1.77). LV unloading with Impella vs IABP was associated with greater risk of AKI requiring HD (OR, 1.49; 95% CI, 1.13-1.97), higher in-hospital mortality (OR, 1.32; 95% CI, 1.10-1.60), and high 40-day mortality (HR, 1.25; 95% CI, 1.17-1.32). Conclusions: LV unloading using Impella, compared with IABP, was not associated with improved survival at 40 days in patients treated with VA-ECMO for CS, but was associated with increased adverse events. These findings suggest a need for further studies to guide clinical practice of LV unloading in CS.