Percutaneous management of Atrial Flow Regulator thrombosis in Failing Fontan- a case report

Background Concomitant thrombosis of the Fontan conduit and atrial flow regulator highlights the marked prothrombotic milieu characteristic of failing Fontan circulation. Case summary We report a case of a 12-year-old with double inlet left ventricle, malposition of the great arteries, with aortic arch hypoplasia who underwent single ventricle palliation with Fontan completion at the age of 7 years old. Over the following years, he developed protein-losing enteropathy associated with ascitic and pleural effusions, therefore fenestration of the Fontan conduit was performed, using an atrial flow regulator. Despite anticoagulation therapy with Rivaroxaban, thrombosis of the atrial flow regulator occurred one month after implantation. The device was retrieved after multiple attempts using a grasping forceps, but conduit thrombosis occurred. Fenestration stenting was performed and thromboaspiration was successfully performed, protecting the systemic circulation with a balloon inflated across the fenestration. At the 6-month follow-up, the patient remained haemodynamically stable, with a patent fenestration and no evidence of visceral effusions. Discussion This case underscores the challenges of managing device-related thrombosis in patients with failing Fontan circulation and demonstrates the potential role of a fully percutaneous treatment strategy.