The Use of Mechanical Circulatory Support Devices in Acute Myocardial Infarction & Cardiogenic Shock

Acute myocardial infarction (AMI) remains a leading cause of cardiovascular-related deaths and is linked with a mortality rate of 30-45% in patients experiencing concurrent cardiogenic shock (CS). Current guidelines from United States medical societies recommend immediate restoration of blood flow for both ST-elevation myocardial infarction (STEMI) and non-ST-elevation myocardial infarction (NSTEMI) patients who have unstable hemodynamics. Those with acute myocardial infarction cardiogenic shock (AMI-CS) are at significant risk of deterioration due to existing left ventricular dysfunction, increased comorbidities, concurrent multi-vessel disease, and complex coronary artery structures. Mechanical circulatory support devices have been used to improve hemodynamics in patients with AMI-CS; however, research has not demonstrated a uniform improvement in outcomes. The IABP has been the traditional device of choice in AMI-CS, with more recent data demonstrating an increase in the use of percutaneous left ventricular assist devices (pLVAD) and extracorporeal membrane oxygenation (ECMO).

Do mechanical circulatory support devices improve mortality in acute myocardial infarction & cardiogenic shock?

• 0%Yes
• 0%No
• 0%I do not know!

An analysis of a retrospective cohort comprising 110,452 patients experiencing AMI-CS who underwent early percutaneous coronary intervention (PCI) revealed that mechanical circulatory support (MCS) was employed in 55% of cases, with the intra-aortic balloon pump (IABP) being the most commonly used device. While the adoption of IABP diminished from 2009 to 2014, there was a simultaneous increase in the utilization of pLVAD and ECMO. MCS-assisted PCI demonstrated a predictive association with increased in-hospital mortality (31% compared to 26%, adjusted odds ratio 1.23 [1.19-1.27]; p<0.001), along with greater utilization of resources. [1].

Jentzer et al

In a recent network meta-analysis involving 11 randomized clinical trials evaluated the efficacy of temporary mechanical circulatory support (MCS) devices in adult patients with acute myocardial infarction cardiogenic shock (AMICS). The trials encompassed a total of 1053 patients, revealing an observed in-hospital or 30-day mortality rate of 40.4%.

Contrary to expectations, the results indicate that none of the temporary MCS devices demonstrated a significant reduction in in-hospital or 30-day mortality when compared to initial medical therapy or other MCS devices, both when examined individually or in combination. Consequently, these findings challenge the conventional notion of employing temporary MCS devices as a routine strategy for mitigating short-term mortality in unselected AMICS patients [2].

REFERENCES:

1. Vallabhajosyula S, Prasad A, Sandhu GS, Bell MR, Gulati R, Eleid MF, Best PJM, Gersh BJ, Singh M, Lerman A, Holmes DR Jr, Rihal CS, Barsness GW; Colaborators. Ten-year trends, predictors and outcomes of mechanical circulatory support in percutaneous coronary intervention for acute myocardial infarction with cardiogenic shock. EuroIntervention. 2021 Feb 5;16(15):e1254-e1261[PubMed].

2. Jentzer et al. Network meta-analysis of temporary mechanical circulatory support in acute myocardial infarction cardiogenic shock. AM Heart J 2023;epublished August 15th [Link].