Background: The use of Impella ventricular support systems and intra-aortic balloon pump (IABP) in acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) has increased in recent years and expanded treatment options, although the comparative clinical outcomes and device safety remain unclear.
Methods: We used the Nationwide Inpatient Sample database (2012-2017) to identify adults who were admitted for AMI complicated by CS and received percutaneous coronary intervention (PCI). The study sample was divided into Impella and IABP groups. Patient characteristics, hospital characteristics, and comorbidities were balanced between groups using propensity-score matching. Regression analysis was utilized to study outcome differences between groups.
Results: We identified 51,150 patients, of whom 44,265 (86.54%) received IABP and 6885 (13.46%) received Impella. After propensity matching, compared with the Impella group (n = 1592), the IABP group (n = 8638) had lower rates of sepsis (6.44% vs 12.69%; P=.01), blood transfusion (8.92% vs 14.28%; P=.01), mortality (28.95% vs 49.59%; P<.01), and hospitalization costs ($49,420 vs $68,087; P<.001). The IABP group had similar rates of cardiac arrest (20.32% vs 22.22%; P=.32), in-hospital stroke (1.46% vs 1.59%; P=.37), and length-of-stay (8.56 days vs 8.64 days; P=.26) compared with the Impella group.
Conclusion: In patients with CS complicating AMI who underwent PCI, Impella use compared with IABP was associated with higher mortality with no differences in in-hospital stroke and cardiac arrest rates, although study interpretation is limited by retrospective observational design and the potential for remaining confounders. Further prospective research is warranted to elucidate the optimal mechanical circulatory support device in these patients.
Keywords: acute myocardial infarction; cardiogenic shock; mechanical circulatory support device; percutaneous coronary intervention.