Influence of intra-aortic balloon pump on mortality as a function of cardiogenic shock severity

Background: Randomized studies of intra-aortic balloon pump (IABP) in cardiogenic shock (CS) have only included on patients with acute coronary syndromes (ACS) without stratification according to shock severity. We examined the association between IABP and mortality in CS patients across the Society for Cardiovascular Angiography and Intervention (SCAI) shock stages. Methods: We included cardiac intensive care unit patients admitted from 2007 to 2015 with CS from any etiology. In-hospital mortality associated with IABP was examined in each SCAI shock stage. Multivariable logistic regression was performed using inverse probability of treatment weighting (IPTW) to determine the association between IABP and in-hospital mortality. Results: We included 934 patients, with a mean age of 68 ± 14 years; 60% had ACS. The distribution of SCAI shock stages was: B, 41%; C, 13%; D, 38%; E, 8%. In-hospital mortality was lower in the 39% of patients who received IABP (27% vs. 43%, adjusted OR with IABP after IPTW 0.53, 95% CI 0.40–0.72, p <.0001). IABP use was associated with lower crude in-hospital mortality in each SCAI shock stage (all p <.05, except p =.08 in SCAI shock stage E). We did not observe any significant heterogeneity in the association between IABP use and in-hospital mortality as a function of SCAI shock stage. Conclusions: Patients with CS who were selected to receive an IABP had lower in-hospital mortality, without differences in this effect across the SCAI shock stages. Future studies should account for the severity and etiology of shock when evaluating the efficacy of IABP for CS.