Modified AngioVac System use With Extracorporeal Membrane Oxygenation in a Child With Fontan Thrombosis

The AngioVac System (AVS) extracts venous and pulmonary artery (PA) thrombi. We report modified use of the second-generation AVS with concurrent venoarterial extracorporeal membrane oxygenation (VA-ECMO) in a 10-year-old, 23 kg patient with failing Fontan circulation due to acute-on-chronic Fontan and PA thrombosis. Emergent femoral VA-ECMO was initiated for profound hypoxemia during cardiac catheterization. Fluoroscopy-guided thrombo-embolectomy was performed with AVS components. A two-venous limb inflow cannulation strategy was used; the AngioVac cannula (AVC) was positioned in the central PA and joined to the existing ECMO venous-limb. Thrombus extraction proceeded by clamping the ECMO venous-limb with the existing VA-ECMO centrifugal pump generating negative pressure to the AVC. Extracorporeal membrane oxygenation arterial-limb access was used for blood return. Settings to avoid cavitation were a maximal negative pressure of 100 mmHg using <3500 RPMs. To access the branch PAs, the AVC was replaced by a custom-modified 17 Fr arterial ECMO cannula. Clot retrieval was sufficient for improved clinical status enabling ECMO discontinuation within 24-hours, and discharge home 26-days later. This is the first description of successful subtotal thrombo-embolectomy with AVS components in a child with Fontan physiology concurrently supported on VA-ECMO, using one centrifugal pump. Although feasible, circuit modifications and close monitoring are required to avoid complications.