Trends in intra-aortic balloon pump use in cardiogenic shock in the post-SHOCK II trial era.

Abstract

Background: Myocardial infarction complicated by cardiogenic shock (MI-CS) has a poor prognosis, even with early revascularisation. Previously, intra-aortic balloon pump (IABP) use was thought to improve outcomes, but the SHOCK-II trial (Intraaortic Balloon Pump in Cardiogenic Shock II) found no survival benefit. Objective: This study determined the trends in IABP use in patients with MI-CS undergoing percutaneous intervention (PCI) over time. Methods: Between 2005 and 2018, patients presenting with MI-CS who underwent PCI at a hospital participating in the Melbourne Interventional Group Registry were included. Results: Of the 1,110 patients identified, IABP was used in 478 (43%). IABP was used more in patients with left main and LAD culprit lesions (62% vs 46%), lower ejection fraction (<35%: 18% vs 11%), and preprocedural inotrope use (81% vs 73%; all p<0.05). IABP use was associated with higher in-patient bleeding (18% vs 13%) and 30-day major adverse cardiovascular and cerebrovascular events (MACCE; 58% vs 51%; both p<0.05). The rate of MI-CS increased over time, but after 2012 there was a decline in IABP use (Figure 1). IABP use was a predictor of 30-day MACCE (odds ratio, 1.6; 95% confidence interval, 1.18–2.29 [p=0.003]). However, IABP was not associated with in-hospital, 30-day, or long-term mortality. Conclusion: Consistent with the SHOCK-II trial, IABP use does not reduce short- or long-term mortality, but in this study was associated with increased short-term adverse events. IABP use is declining but is still used in sicker patients with greater myocardium at risk, given limited alternatives.