Extra corporeal membrane oxygenation in the therapy of cardiogenic shock (ECMO‐CS): rationale and design of the multicenter randomized trial

Abstract

Aims Extracorporeal membrane oxygenation (ECMO) in veno‐arterial configuration represents an increasingly used method for circulatory support. ECMO in cardiogenic shock offers rapid improvement of circulatory status and significant increase in tissue perfusion. Current evidence on the use of ECMO in cardiogenic shock remains insufficient. The aim of the ECMO‐CS trial is to compare two recognized therapeutic approaches in the management of severe cardiogenic shock: early conservative therapy and early implantation of veno‐arterial ECMO on the background of standard care. Methods Eligible patients have either rapidly deteriorating or severe cardiogenic shock, defined using echocardiography, hemodynamic and metabolic criteria. Patients are randomized to the one of two arms: immediate veno‐arterial ECMO therapy or early conservative therapy. All other diagnostic and therapeutic procedures are performed as per current standard of care, including other cardiovascular interventions (i.e. percutaneous coronary intervention or cardiac surgery). Follow‐up includes visits at 30 days, 6 months and 12 months. Primary endpoint is a composite of death from any cause, resuscitated circulatory arrest, and implantation of another mechanical circulatory support device at 30 days. The sample size of 120 individuals (60 in each arm) provides 80% power to detect 50% reduction of primary endpoint, at alpha = 0.05. Patient recruitment started in October 2014. Conclusion The results of the ECMO‐CS trial may significantly influence current practice in the management of patients with severe and rapidly deteriorating cardiogenic shock. ECMO‐CS trial registration number is NCT02301819.

Improved Outcomes Associated with the use of Shock Protocols: Updates from the National Cardiogenic Shock Initiative

“…Multiple trials have shown that intra-aortic balloon pump (IABP) counterpulsation provides insufficient support in AMICS to improve survival and therefore many clinicians have opted to use more robust MCS devices such as Impella (Abiomed, Danvers, MA), Tandem Heart (Cardiac Assist Inc, Pittsburgh, PA), and veno-arterial extracorporeal membrane oxygenation (VA-ECMO). [3][4][5][6] In 2016, the Food and Drug Administration (FDA) approved Impella, a percutaneous microaxial MCS device, for use in patients with cardiogenic shock. The basis of Impella's FDA approval and increasing use in the United States has been significant improvements in hemodynamics when compared with IABP.…”

Extracorporeal membrane oxygenation in the therapy of cardiogenic shock (ECMO‐CS): the need for a better definition of refractory cardiogenic shock

“…On the other hand, MCS implantation including ECMO is allowed in the conservative arm ‘in case of shock progression, i.e. rapid deterioration of haemodynamic or metabolic status (defined as a need for increasing doses of vasopressor or a rise of serum lactate by 3 mmol/L within a minimum of 30 minutes after randomization)’ . The deterioration is only vague and should be more strictly defined, in a way in which no one would dispute the imperative to implant ECMO unless letting the patient die.…”

“…As previously published, one could imagine a trial of MCS for patients with signs of tissue hypoxia (or arrhythmias) and CRASH score < 0.0375 (a way to reproducibly define refractory CS) in the intervention arm, vs. either no MCS (last resort conception), or very restrictive reproducible criteria (including CRASH score < 0.0300 for example) . In their study, the Authors plan to include severely compromised patients (cardiac index <2.2 L/min/m 2 or systolic blood pressure <100 mmHg, that may be evaluated at about cardiac power index <0.3 W/m 2 ) who do not respond to moderate doses of catecholamine (inotropic score > 15 to >25). Thus they barely aim to maintain CRASH score ≥ 0.06.…”

“…7 Those three expert centres that try to surmount the challenge of designing a RCT of extracorporeal membrane oxygenation in the therapy of cardiogenic shock (ECMO-CS) have to be commended. 8 They judiciously decided to exclude obstructive shock (mainly pulmonary embolism), where ECMO definitely has a role in severe cases. However, high-risk pulmonary embolism carries a different prognosis and should be evaluated in another RCT.…”

“…rapid deterioration of haemodynamic or metabolic status (defined as a need for increasing doses of vasopressor or a rise of serum lactate by 3 mmol/L within a minimum of 30 minutes after randomization)'. 8 The deterioration is only vague and should be more strictly defined, in a way in which no one would dispute the imperative to implant ECMO unless letting the patient die. If epinephrine is allowed, how should the serum lactate level be handled?…”