Effect of intra-aortic balloon pump on in-hospital mortality in acute myocardial infarction complicating cardiogenic shock at different stages.

Background: In 2012, the randomised trial IABP SHOCK II demonstrated that IABP did not reduce 30-day mortality in patients with acute myocardial infarction complicating cardiogenic shock (CS). However, SCAI proposed a new standardised classification of cardiogenic shock in 2019. It is reasonably hypothesised that the use of IABP may have different benefits for patients in different stages of CS.

Methods: AMI patients ≥18 years who had received treatment of implantation of IABP during emergency setting in Beijing Chaoyang Hospital between December 2010 and July 2021 were enrolled in this study. CS stages were classified at admission for all eligible cases. During the same period, AMI patients without implantation of IABP were matched with each stage of CS above using propensity score matching (PSM). Data were as follows: Stage B (n = 302), Stage C (n = 290), Stage D (n = 68), and Stage E (n = 32). In-hospital mortality was compared between using and without using IABP at each stage.

Results: In stage C, the in-hospital mortality was significantly lower in the IABP group (31/145, 21.4%) than in the group without IABP (47/145, 32.4%) (OR 0.567, 95% CI, p = .034). In-hospital mortality had no significant difference between use and no-use of IABP in stage B (16.6% vs 14.6%, p = .634), stage D (47.1% vs 38.2%, p = .462), and in stage E (81.3%vs 68.8%, p = .414).

Conclusions: For patients with acute myocardial infarction complicating cardiogenic shock, IABP has no effect on in-hospital mortality in SCAI stages B, D, and E. However, in SCAI stage C, IABP can reduce in-hospital mortality.