New Study Challenges Use of ECMO for MI-Related Shock, Revealing No Survival Advantage, Increased Risks
A recent study has called into question the routine use of extracorporeal membrane oxygenation (ECMO) in patients with acute myocardial infarction (MI) and shock. The study, called ECLS-SHOCK, found that there was no significant survival advantage for patients who received ECMO compared to those who received standard care. In fact, patients on ECMO experienced a higher risk of moderate and severe bleeding and vascular complications.
The use of ECMO in MI-related shock has been supported by observational data and guidelines that promote mechanical circulatory support. However, the findings of the ECLS-SHOCK trial highlight the lack of evidence to support this approach. Lead author Holger Thiele, MD, from the Heart Center Leipzig, Germany, presented the trial at the European Society of Cardiology (ESC) 2023 Congress.
The trial randomly assigned 420 patients with acute MI complicated by shock to receive either standard care or early ECMO. The primary endpoint of all-cause mortality at 30 days showed no significant difference between the two groups, with a mortality rate of approximately 48% for both. However, patients on ECMO had a significantly higher risk of moderate or severe bleeding and vascular complications.
The results of the ECLS-SHOCK trial are consistent with a meta-analysis of ECMO trials in MI-related shock, which also showed increases in bleeding with survival gains. In light of these findings, experts suggest that the routine use of ECMO in all patients with MI-related shock should be reconsidered. They emphasize the need for further studies to identify which patients would truly benefit from this intervention.
Notably, subgroup analyses in both the ECLS-SHOCK trial and the meta-analysis did not identify any specific groups that benefited from ECMO. According to Thiele, if there is a subgroup that may benefit, it is likely less than 1% of patients.
This news challenges the current clinical practice surrounding ECMO use in MI-related shock. While there may be some patients for whom ECMO is necessary and lifesaving, the ECLS-SHOCK trial does not provide clear guidance on who those patients are. Further research is needed to identify the specific criteria for selecting patients who would benefit the most from ECMO.
Experts caution against the early routine implementation of ECMO for all or most patients with myocardial infarction and cardiogenic shock. The results of the ECLS-SHOCK trial should guide interventional and critical care cardiologists away from this approach if the goal is to improve 30-day mortality. Instead, ECMO should be reserved for patients with infarct-related cardiogenic shock in whom the potential benefits outweigh the potential harms.
