What are the considerations for weaning from Extracorporeal Membrane Oxygenation (ECMO) support in a patient with myocarditis?

From the Guidelines

Weaning from ECMO support in myocarditis should be considered when there are signs of ventricular recovery, and can be performed by assessing clinical parameters such as hemodynamics and echocardiographic left ventricular function. According to the American Heart Association, patients who receive nondurable MCS, such as ECMO, should always be evaluated for possible ventricular recovery, particularly in the setting of myocarditis 1. When weaning from ECMO, it is essential to monitor clinical parameters, including hemodynamics and echocardiographic left ventricular function.

• Key indicators of myocardial recovery include:
  • Improved ejection fraction
  • Decreasing cardiac biomarkers
  • Reduced vasopressor requirements
  • Stable hemodynamics
• The weaning process typically involves gradually reducing ECMO flow while monitoring hemodynamic parameters, and may require pharmacological support with inotropes and vasopressors as needed.
• Echocardiographic assessment should be performed regularly to evaluate ventricular function, and anticoagulation with heparin should be maintained during weaning, targeting an appropriate aPTT or anti-Xa level.
• A trial off period with ECMO flow at minimal levels can confirm readiness for decannulation, and following successful weaning, patients typically require continued cardiac support with oral heart failure medications.

From the Research

Weaning from ECMO Support in Myocarditis

• The process of weaning from ECMO support in patients with myocarditis is crucial for their recovery and outcomes 2, 3.
• Echocardiography plays a significant role in monitoring cardiac function and complications during ECMO support, as well as in predicting the success of weaning 3.
• Parameters such as aortic VTI ≥ 10 cm, LVEF > 20-25%, and lateral mitral annulus peak systolic velocity > 6 cm/s have been identified as predictors of successful weaning 3.
• Studies have shown that VA-ECMO support can be effective in treating fulminant myocarditis, with a one-year post-hospital survival rate ranging from 57.1% to 78% at discharge 4.
• However, the optimal length of time a patient should be placed on VA-ECMO is still unclear, and more research is needed to determine the efficacy of VA-ECMO for the treatment of fulminant myocarditis 4.

Complications and Risk Factors

• Major complications may occur during ECMO support, including acute renal failure, sepsis, pulmonary infection, multiple organ failure, cerebral hemorrhage, and limb ischemia 2, 5.
• Pre-ECMO cardiopulmonary resuscitation, high levels of lactic acid, high amounts of blood transfusion during ECMO, renal failure, encephalorrhagia, gastrointestinal complications, lower-limb ischemia, high bilirubin levels, and MOF during ECMO have been associated with unfavorable patient outcomes 5.
• Improving tissue perfusion, reducing blood transfusions, and preventing acute kidney failure may improve patient outcomes 5.

Outcomes and Survival Rates

• The pooled short-term mortality for patients with fulminant myocarditis supported with VA-ECMO was 35% (95% CI 29-40%) 6.
• The 5-year actual survival rate for patients with acute fulminant myocarditis treated with VA-ECMO was 65.2% ± 7.9% 2.
• Long-term outcome appears favorable with rare episodes of recurrent myocarditis or cardiac-related events 2.