The impact of traditional vs parallel venous-arterial extracorporeal membrane oxygenation on the intra-aortic hemodynamic environment: A numerical study

To investigate the impacts of traditional and parallel venous-arterial extracorporeal membrane oxygenation (TVA and PVA-ECMO) cannulation modes on the aortic hemodynamic surroundings under differential cardiac conditions. Clinical imaging data were utilized to build the numerical models. Computational fluid dynamics methods were applied to analyze five aortic models with VA-ECMO implantation, including one TVA-ECMO and four PVA-ECMO configurations with distinct cannulation positions, under four conditions of cardiac insufficiency. Evaluation parameters included standard hemodynamic parameters, hyperoxic blood distribution, residence time, and shear stress. The distribution of oxygen saturation distribution, hemolysis risk, and thrombosis risk were assessed using our newly constructed numerical models. When cardiac function was partially recovered, the boundaries of the mixed zone of hyperoxic and hypoxic blood were all located in the upper limb of the aorta. The location of the mixing zone shifted toward the distal aorta when TVA-ECMO was converted to P1 VA-ECMO. Increasing the depth of cannula placement improved perfusion of hyperoxic blood in all aortic arch branches. Lower ECMO perfusion levels in the same cannulation model correlated with decreased wall shear stress and scalar shear stress in the aorta, alongside reduced hemolysis levels. Changing TVA-ECMO to P1 VA-ECMO increased intra-aortic thrombosis risk, which decreased with deeper additional cannula placements from P2 to P4 in PVA-ECMO configurations. Transitioning from TVA to PVA-ECMO enhances ECMO support and diminishes ECMO-related complications (hemolysis and thrombosis) when the PVA-ECMO cannula is appropriately positioned. Coronary aerobic hypoperfusion persists with both TVA and PVA-ECMO upon partial cardiac function recovery. This study can provide guidance for the selection of different annulation strategies in VAECMO treatment.