Intra-aortic balloon pump versus medical management for acute myocardial infarction complicated by cardiogenic shock: a retrospective cohort analysis

BACKGROUND: Acute myocardial infarction complicated by cardiogenic shock (AMI-CS) carries the highest in-hospital mortality among acute coronary syndromes, with medical management and various adjunctive therapies employed to care for these critically-ill patients. OBJECTIVE: Intra-aortic balloon pumps (IABP) are a widely-used therapy, thus we aim to evaluate differences in mortality, clinical outcomes, and hospital courses of patients with AMI-CS treated with IABP versus non-IABP medical management. METHODS: We conducted a retrospective cohort study of the National Inpatient Sample database between October 2015 and December 2022, including patients ≥18 years-old hospitalized with AMI and subsequent CS. Propensity score-based inverse probability of treatment weighting and multivariable logistic regression estimated adjusted odds ratios (aORs) with 95% confidence intervals (CIs). RESULTS: Among 247,825 AMI-CS hospitalizations, 84,635 (34.2%) involved IABP. IABP was associated with lower odds of both routine discharge (aOR: 0.837, 95% CI [0.794-0.882], p < 0.001) and inpatient mortality (0.653[0.623-0.684], p < 0.001), increased thrombocytopenia (2.10[1.98-2.22], p < 0.001) and lower acute kidney injury (0.816[0.783-0.849], p < 0.001). These patients also had higher odds of papillary muscle rupture (3.58[2.50-5.12], p < 0.001) and left ventricular wall rupture (1.67[1.17-2.39], p = 0.005). CONCLUSIONS: Despite greater baseline sickness, IABP was linked with a significant inpatient mortality reduction in AMI-CS. Increased thrombocytopenia and non-routine discharge potentially reflect treatment-related morbidity as a result of survivorship bias compared to patients receiving medical management alone. Prospective studies are needed to refine patient selection and mitigate device-related complications.