Effect of mechanical circulatory support on outcomes in patients with cardiogenic shock secondary to acute myocardial infarction

Abstract

The outcomes of mechanical circulatory support (MCS) in patients with cardiogenic shock (CS) following acute myocardial infarction (AMI) are controversial. We included 1513 patients from six Gulf countries with AMI and CS between 2020 and 2022. Eight hundred twenty patients did not receive MCS, and 693 received MCS, predominantly via an intra-aortic balloon pump (IABP). Patients receiving MCS were more critically ill, with 94.95% in SCAI shock stages D or E versus 46.95% in the non-MCS group. While unadjusted in-hospital mortality was significantly higher in the MCS group (61.0% vs. 32.2%; p < 0.001), this difference was attributable to baseline risk. In a propensity score-matched analysis of 430 patient pairs, there was no significant difference in in-hospital mortality (46.7% vs. 43.7%; p = 0.429 for PCI patients) or long-term survival. Mortality was not related to the time of MCS initiation. Among patients with SCAI Stages D and E, the use of MCS was not associated with improved short- or long-term clinical outcomes. The findings, driven by a predominantly IABP-based MCS strategy, suggest that the higher observed mortality in patients receiving MCS reflects their greater illness severity, and that a survival benefit for this MCS approach was not demonstrated. This underscores the need for patient selection and timing of MCS to optimize outcomes.