The ECMO-CS Trial: New Insights Into the Treatment of Cardiogenic Shock

By Amy E. Hackmann, M.D.

Associate Professor of Cardiovascular and Thoracic Surgery
Surgical Director, ECMO Program

The optimal approach for treating critically ill patients with cardiogenic shock remains uncertain. The Extracorporeal Membrane Oxygenation in the Therapy of Cardiogenic Shock (ECMO-CS) trial, presented at #AHA22 by Petr Ostadal, M.D., Ph.D., tested whether immediate versus not immediate initiation of ECMO improved outcomes in this patient population.

ECMO-CS was a multicenter, randomized, unblinded, small (N=122) trial of cardiogenic shock management conducted in the Czech Republic. The patients enrolled had rapidly deteriorating cardiogenic shock or SCAI stage D-E shock and were randomized to immediate vs. no immediate ECMO support. The characteristics between treatment groups were similar: the average age was 66 years, and 73% were male. Most (62%) trial participants had cardiogenic shock related to acute myocardial infarction, while 24% had shock superimposed on prior chronic heart failure. 14% had an intra-aortic balloon pump in place at the time of randomization. 72% of participants required mechanical ventilation prior to study enrollment.

After randomization, both hemodynamic and laboratory parameters – including blood pressure, cardiac index, mixed venous oxygen saturation, and lactate – were monitored to assess responsiveness to therapy. A rise of serum lactate by 3 mmol/L vs. the lowest value in the preceding 24 hours was required to escalate to VA-ECMO implementation in the no immediate ECMO arm. No limitation was placed on the use of additional therapies, and nearly 40% of patients in the no immediate ECMO arm ultimately received VA-ECMO.

Mortality and complication rates were similar between the two groups; half of patients died within one month of study enrollment. Rates of complications such as bleeding, lower extremity ischemia, and stroke were no different between treatment arms.

In this small, randomized trial, no harm was demonstrated with a strategy predicated on the initial use of inopressors with escalation to ECMO only if a patient with cardiogenic shock deteriorated further as ascertained by a rise in serum lactate. In clinical practice, when ECMO is not initiated upfront, hemodynamic and laboratory parameters should be monitored closely, as done in the ECMO-CS trial, to identify deterioration despite inopressors so that appropriate patients can be rescued by escalation to VA-ECMO.

Tweets by @ECMONinja