Table 1 Summary of the included studies

Thiele et al. 2023

Germany, Slovenia

Phase 3, Open-label RCT

ECLS began during index catheterization, preferably before PCI. An antegrade arterial femoral sheath was advised to reduce the risk of lower limb ischemia.

The study protocol forbade control group to ECLS crossover.

An intraaortic balloon pump or microaxial transvalvular flow pump can be used for escalation therapy under certain hemodynamic circumstances. These criteria included severe hemodynamic instability with impending collapse, a 6-hour arterial lactate elevation of more than 3 mmol per liter, or a 50% increase in vasopressor use from baseline to maintain a mean arterial blood pressure over 65 mm Hg.

I. Hemodynamic stability means sustained systolic blood pressure > 90 mmHg or mean blood pressure > 65 mmHg (> 60 min).

II. Persistent ejection with little inotropic support

III. No severe hypoxemia

IV. Arterial lactate < 2 mmol/l

V. Central venous saturation > 65%

ECLS flow should be reduced by 0.5-1.0 l/min over 4–6 h if the conditions are met.

Successful weaning with subsequent ECLS removal was defined as flow reduction to 1.0-1.5 l/min.

Removal was to be performed according to local expertise.

Percutaneous closure was recommended

30 days

Ostadal et al. 2022 (ECMO-CS)

Czech Republic

Phase 3, Open-label RCT

Except for immediate VA-ECMO implementation in the intervention group, all other diagnostic and therapeutic procedures were performed according to current standards, including percutaneous coronary or noncoronary intervention, cardiac surgery, and mechanical circulatory support.

If serum lactate rises by 3 mmol/L from the lowest value in the last 24 h, VA-ECMO may be utilized downstream in the early conservative group.

The protocol did not specify left ventricular venting during VA-ECMO support or limb ischemia prevention or treatment and were left to physicians.

NA

30 days

Banning et al. 2023 (EURO SHOCK)

Spain, Germany, United Kingdom, Norway, Latvia, Belgium

Open-label RCT

Intra-aortic balloon pump (IABP) use was permitted as a left ventricular unloading in patients receiving VA-ECMO therapy.

IABP was allowed in the control therapy group, but mechanical support devices were discouraged. However, it was permitted if the physicians felt it would help in clinically deteriorated cases and acknowledged as procedural violation.

Removal was to be performed according to local expertise and the patient’s clinical status by intensive care physicians.

30-days and 1-year.

Lackermair et al. 2020 (ECLS-Shock-I)

Germany

phase 4, Open-label RCT

ECLS implantation was performed in the catheterization laboratory under fluoroscopic control. To prevent lower limb ischemia, a distal limb perfusion cannula was inserted into the superficial femoral artery. Stöckert Centrifugal Pump System (SCP, LivaNova, Munich, Germany) used for mechanical circulation support.

NA

Weaning was done after sustained hemodynamic stabilization on low levels of inotropic and vasopressor support with sufficient peripheral perfusion and end-organ function had been achieved.

30-days and 1-year.