Benefit of Extracorporeal Membrane Oxygenation before Revascularization in Patients with Acute Myocardial Infarction Complicated by Profound Cardiogenic Shock after Resuscitated Cardiac Arrest

BACKGROUND AND OBJECTIVES: The study sought to investigate the impact of early extracorporeal membrane oxygenation (ECMO) support before revascularization in patients with acute myocardial infarction (AMI) complicated by profound cardiogenic shock after resuscitated cardiac arrest. It is difficult to determine optimal timing of ECMO in patients with AMI complicated by profound cardiogenic shock after resuscitated cardiac arrest. METHODS: Among 116,374 patients experiencing out-of-hospital cardiac arrest in South Korea, a total of 184 resuscitated patients with AMI complicated by profound cardiogenic shock, and who were treated successfully with percutaneous coronary intervention (PCI) and ECMO, were enrolled. Patients were divided into 2 groups according to the timing of ECMO: pre-PCI ECMO (n=117) and post-PCI ECMO (n=67). We compared 30-day mortality between the 2 groups. RESULTS: In-hospital mortality was 78.8% in the entire study population and significantly lower in the pre-PCI ECMO group (73.5% vs. 88.1%, p=0.020). Thirty-day mortality was also lower in the pre-PCI ECMO group compared to the post-PCI ECMO group (74.4% vs. 91.0%; adjusted hazard ratio [HR], 0.66; 95% confidence interval [CI], 0.47–0.93; p=0.017). Shockable rhythm at the emergency room (HR, 0.57; 95% CI, 0.36–0.91; p=0.019) and successful therapeutic hypothermia (HR, 0.40; 95% CI, 0.23–0.69; p=0.001) were also associated with improved 30-day survival. CONCLUSIONS: ECMO support before revascularization was associated with an improved short-term survival rate compared to ECMO after revascularization in patients with AMI complicated by profound cardiogenic shock after resuscitated cardiac arrest.