Cardiogenic shock is a common complication in patients who present with acute myocardial infarction (AMI) and is the leading cause of death in this population.¹ Even with immediate revascularization, death rates remain high. The use of extracorporeal life support (ECLS) has risen in frequency over the previous 10 years, but evidence for its use to improve outcomes remains lacking.

The ECLS-SHOCK (ExtraCorporeal Life Support for acute myocardial infarction complicated by cardiogenic shock) trial was a randomized, multicenter, open-label trial that assessed the hypothesis that early ECLS treatment, compared with usual medical therapy alone, would result in improved survival in patients with AMI complicated by cardiogenic shock for whom early revascularization was planned.² Study patients had evidence of hypotension and hypoperfusion with arterial lactate level >3 mmol/L. The primary outcome was death from any cause at 30 days. Safety outcomes included bleeding, stroke, and peripheral vascular complications warranting intervention or surgical therapy. The 30-day results included: death from any cause in 100 (47.8%) of the 209 ECLS patients and in 102 (49%) of the 208 control patients. Refractory cardiogenic shock was the leading cause of death in both groups. Because of refractory shock, ECLS was initiated in 26 (12.5%) control patients. The safety outcomes of moderate to severe bleeding and peripheral vascular complications were more common in the ECLS group.

In summary, in patients with AMI complicated by cardiogenic shock, the incidence of death from any cause at 30 days was not lower among those receiving early unselective ECLS than among those receiving usual medical treatment. Some limitations of the study include group crossover and a low rate (5.8%) of left ventricular unloading in the ECLS group. The optimal role and timing of ECLS in cardiogenic shock remains elusive and further studies are needed.

References

1. Samsky MD, Morrow DA, Proudfoot AG, Hockman JS, Thiele H, Rao SV. Cardiogenic shock after acute myocardial infarction: a review. JAMA 2021;326:1840-50.
2. Thiele H, Zeymer U, Akin I, et al.; ECLS-SHOCK Investigators. Extracorporeal life support in infarct-related cardiogenic shock. N Engl J Med 2023;389:1286-97.