Abstract Body (Do not enter title and authors here):
Introduction: Temporary mechanical circulatory support (tMCS) devices such as intra-aortic balloon pump (IABP) and Impella are commonly used to stabilize patients with cardiogenic shock (CS). While recent evidence supports their role in myocardial infarction (MI)-related CS, data in non-MI CS, particularly regarding newer Impella devices like the Impella 5.5, remain limited.

Aim: We aimed to compare outcomes associated with IABP versus various Impella devices in non-MI CS using a large, nationally representative dataset.

Methods: We conducted a retrospective analysis of the National Inpatient Sample (NIS) database from 2016–2022, identifying patients with non-MI CS who received IABP, Impella 2.5/CP, or Impella 5.0/LD/5.5. To adjust for confounding factors, propensity score matching was performed. Outcomes included in-hospital mortality, rates of orthotopic heart transplant (OHT) and durable left ventricular assist device (LVAD) implantation, blood transfusion requirements, length of stay, and total hospital charges.

Results: A total of 9,914 cases were identified, including 7,214 patients who received IABP, 2,317 who received Impella 2.5/CP, and 383 who received Impella 5.0/LD/5.5. After propensity score matching, among patients with non-MI CS, use of Impella 5.0/LD/5.5 was associated with lower in-hospital mortality compared to IABP (8.2% vs. 14.9%, p=0.006) and significantly higher rates of OHT (27.6% vs. 11.7%, p<0.001) and LVAD implantation (45.1% vs. 15.6%, p<0.001). However, Impella 5.0/LD/5.5 use was linked to longer hospital stays (40.4 vs. 23.5 days, p<0.001), increased transfusion requirements (21.8% vs. 13.5%, p=0.004), and substantially higher total charges ($1,350,236 vs. $653,962, p<0.001), consistent with findings before matching (all p<0.05).
In contrast, use of Impella 2.5/CP was associated with higher in-hospital mortality (39.6% vs. 23.6%, p<0.001), lower rates of OHT and LVAD implantation, shorter hospital stays (11.2 vs. 17.5 days, p<0.001), and lower total charges ($416,416 vs. $486,318, p<0.001) compared to IABP after matching. These trends were consistent with findings before matching (all p<0.05).

Conclusions: In non-MI CS, the newer-generation Impella 5.0/LD/5.5, but not the Impella 2.5/CP, was associated with improved survival and higher rates of advanced therapies (OHT and LVAD) compared to IABP, though at the expense of increased transfusion requirements, longer hospitalization, and greater resource utilization.