A56-08 Comparative Outcomes of Impella Versus Intra-Aortic Balloon Pump Support During Coronary Artery Bypass Grafting: Evidence From the National Inpatient Sample Database

Rationale Mechanical circulatory support (MCS) devices are increasingly employed to optimize hemodynamic stability in patients undergoing coronary artery bypass grafting (CABG). While the intra-aortic balloon pump (IABP) has long represented the conventional support strategy, the Impella device offers active left ventricular unloading and cardiac output augmentation. Despite its expanding utilization, comparative outcome data for Impella versus IABP use during CABG remains limited. This study aimed to evaluate national-level differences between these two MCS modalities. Methods A retrospective cohort analysis was performed using the 2020 National Inpatient Sample (NIS) database. Adult patients (≥18 years) who underwent CABG with either Impella or IABP support were identified using ICD-10 procedure codes. Primary outcomes included in-hospital mortality, length of stay (LOS), and total hospitalization charges. Secondary outcomes encompassed major complications and discharge disposition. Survey-weighted logistic and linear regression models adjusted for demographics, comorbidities, and hospital characteristics were applied. Propensity-based inverse probability of treatment weighting (IPTW) and doubly robust models were employed to minimize confounding. Statistical significance was defined as p < 0.05. Results Among 3,300 weighted hospitalizations involving CABG with MCS, 2,927 (88.7%) received IABP and 373 (11.3%) received Impella. Median age was 67 years in both groups (p = 0.015), but Impella recipients demonstrated higher comorbidity burden (median Elixhauser 6 [5-8] vs 6 [4-7], p < 0.001). Impella support was associated with longer hospital stays (median 15 vs 10 days, p < 10⁻8) and higher total charges ($586,899 vs $280,157, p < 10⁻75). Unadjusted mortality was substantially higher with Impella (35.6% vs 8.7%), along with increased rates of stroke (8.7% vs 4.3%), acute kidney injury (61.3% vs 38.9%), sepsis (16.2% vs 7.2%), cardiogenic shock (60.5% vs 37.8%), and ECMO use (22.1% vs 7.7%). After multivariable adjustment, Impella use remained independently associated with higher mortality (OR 6.23, 95% CI 4.77-8.13), stroke (OR 2.25), AKI (OR 2.82), sepsis (OR 2.49), prolonged LOS (+6.93 days), and 112% higher charges (p < 10⁻58). Findings were confirmed in doubly robust analyses and across comorbidity and hospital subgroups. Conclusions In this contemporary national cohort, the use of Impella during CABG was linked to markedly increased in-hospital mortality, complications, and resource use compared to IABP, even after thorough adjustments. These findings highlight the necessity for future, risk-based assessment of Impella’s function in surgical revascularization. This abstract is funded by: None