What are the management strategies for a patient undergoing Veno-Arterial (VA) Extracorporeal Membrane Oxygenation (ECMO) during right atrial thrombus thrombectomy?

VA ECMO Management During Right Atrial Thrombus Thrombectomy

Anticoagulation Strategy During the Procedure

For right atrial thrombus thrombectomy in a patient on VA-ECMO, anticoagulation should be temporarily reduced or held during the procedure to minimize bleeding risk, with hemodynamic support maintained by the ECMO circuit, then carefully resumed post-procedure with close monitoring. 1, 2

Pre-Procedural Anticoagulation Management

• Reduce or temporarily pause systemic heparin anticoagulation immediately before and during the thrombectomy procedure to minimize surgical site bleeding, as bleeding from surgical sites occurs in 36% of patients receiving therapeutic-dose heparin on VA-ECMO 1

• Consider that severe bleeding complications are significantly lower without anticoagulation (11.5%) compared to therapeutic UFH (32%) during high-risk procedures 1

• Maintain ECMO circuit patency during the anticoagulation pause, as recent evidence shows no difference in thrombotic complications (13% vs 21%) between anticoagulated and non-anticoagulated VA-ECMO patients during short-term holds 1

Hemodynamic Support Settings

• Maintain full VA-ECMO flow support throughout the thrombectomy procedure to ensure hemodynamic stability, as catheter-induced embolization of clots can cause transient hemodynamic compromise 2, 3

• Keep continuous arterial blood pressure monitoring and ECMO flow recording active during the procedure 4

• Ensure adequate ECMO flow rates to support circulation independently, as the procedure may temporarily worsen right heart function if clot fragments mobilize 2, 5

Procedural Considerations

• VA-ECMO provides critical hemodynamic support during high-risk thrombectomy, preventing cardiovascular collapse from catheter-induced clot mobilization from the vena cava or right atrium 2, 3

• The ECMO circuit maintains circulation even if the thrombectomy procedure causes transient worsening of right ventricular function 3, 5

• Case reports demonstrate successful outcomes using mechanical thrombectomy devices (FlowTriever, AngioJet) under VA-ECMO support for right atrial thrombi 2, 3, 5

Post-Procedural Anticoagulation Management

Resumption of Anticoagulation

• Restart anticoagulation at lower doses after achieving hemostasis, typically beginning several hours post-procedure once surgical site bleeding is controlled 6

• Monitor coagulation parameters (aPTT or ACT) closely during the restart phase 6, 7

• Balance the 22.9% risk of thrombotic complications when anticoagulation is withheld against ongoing bleeding risk 6

Monitoring Strategy

• Use aPTT-guided anticoagulation monitoring rather than ACT-guided protocols for VA-ECMO patients, as aPTT correlates better with heparin dosing (r = 0.43-0.54) compared to ACT (r = 0.11-0.14) 1, 7

• Anti-Xa-based anticoagulation monitoring is associated with fewer bleeding events (34.2% vs 41.6%) and lower mortality (35.4% vs 42.9%) compared to time-based strategies 1

• Target anti-Xa activity below 0.46 IU/mL to reduce bleeding risk, as values above this threshold are associated with reduced survival without bleeding 1

• Perform repeated echocardiography to assess right ventricular function recovery and detect any residual thrombus 4

Critical Pitfalls to Avoid

• Do not maintain therapeutic anticoagulation during active thrombectomy, as this increases surgical site bleeding from 21% to 36% 1

• Do not allow ECMO flows to decrease during the procedure, as clot mobilization can cause acute hemodynamic deterioration requiring full circulatory support 2, 3

• Do not restart anticoagulation at full therapeutic doses immediately post-procedure; begin with lower doses and titrate based on bleeding control 6

• Avoid prolonged anticoagulation holds beyond what is necessary for hemostasis, as 42% of ECMO patients experience thrombotic events and 21% experience both bleeding and thrombosis 1, 8

• Monitor for heparin-induced thrombocytopenia (HIT), which occurs in 8% of anticoagulated VA-ECMO patients, and switch to direct thrombin inhibitors if suspected 1

Blood Product Support

• Maintain packed red blood cells available for transfusion, as patients on VA-ECMO with anticoagulation require significantly more transfusions (median 12.8 units) compared to those without (1.09 units) 1

• Have fresh frozen plasma and platelets readily available for coagulopathy management if significant bleeding occurs 6

• Avoid hypothermia during the procedure, as this worsens coagulopathy and increases bleeding risk 6