Escalation strategies, management, and outcomes of acute myocardial infarction-cardiogenic shock patients receiving percutaneous left ventricular support.

Background: There are limited national-level data on the contemporary practices of mechanical circulatory support (MCS) use in acute myocardial infarction-cardiogenic shock (AMI-CS).

Methods: We utilized the Healthcare Cost and Utilization Project-National/Nationwide Inpatient Sample data (2005-2017) to identify adult admissions (>18 years) with AMI-CS. MCS devices were classified as intra-aortic balloon pump (IABP), percutaneous left ventricular assist devices (pLVAD), or extracorporeal membrane oxygenation (ECMO). We evaluated trends in the initial device used (IABP alone, pLVAD alone or ≥2 MCS devices), device escalation, bridging to durable LVAD/heart transplantation, and predictors of in-hospital mortality and device escalation.

Results: Among 327,283 AMI-CS admissions, 131,435 (40.2%) had an MCS device placed with available information on timing of placement. IABP, pLVAD, and ≥2 MCS devices were used as initial device in 120,928 (92.0%), 8202 (6.2%), and 2305 (1.7%) admissions, respectively. Most admissions were maintained on the initial MCS device with 1%-1.5% being escalated (IABP to pLVAD/ECMO, pLVAD to ECMO). Urban, medium, and large-sized hospitals and acute multiorgan failure were significant independent predictors of MCS escalation. In admissions receiving MCS, escalation of MCS device was associated with higher in-hospital mortality (adjusted odds ratio: 1.56, 95% confidence interval:  1.38-1.75; p < 0.001). Admissions receiving durable LVAD/heart transplantation increased over time in those initiated on pLVAD and ≥2 MCS devices, resulting in lower in-hospital mortality.

Conclusions: In this 13-year study, escalation of MCS in AMI-CS was associated with higher in-hospital mortality suggestive of higher acuity of illness. The increase in number of durable LVAD/heart transplantations alludes to the role of MCS as successful bridge strategies.