Transcatheter thrombectomy of acute pulmonary embolism in an adult Fontan patient: a case report

Background The Fontan operation is a well-described palliative procedure for functional single-ventricle patients. This population has an increased risk of thrombo-embolic events. Adequate imaging, and therefore diagnosis, requires an understanding of the unique anatomy and physiology of a Fontan. Optimal strategies for the prevention and treatment of thrombo-embolic complications in the Fontan population are poorly defined.Case summary A 28-year-old female with a history of Ebstein anomaly of the tricuspid valve status post-Fontan presented with chest pain and acute hypoxia. Computed tomographic angiography (CTA) reported a submassive pulmonary embolism (PE). She was initiated on a heparin drip. Catheterization demonstrated elevated Fontan pressures and a large thrombus in the right lower pulmonary artery that was removed with an aspiration device. The patient was transitioned to a direct oral anticoagulant (DOAC) following the procedure.Discussion Thrombotic complications are common in the adult Fontan population. Given the morbidity and mortality associated with this complication, the use of proper imaging techniques is imperative. Traditional CTA imaging for PE in Fontan patients often has contrast filling defects related to their anatomy and physiology. Utilization of adequate imaging techniques helps decrease cost and additional radiation exposure. In addition, it avoids inappropriate hospitalization, need for anticoagulation, and potential need for catheterization toconfirm or exclude the presence of PE. For Fontan patients with a thrombus, prior event, and no contraindications, current guidelines recommend oral anticoagulation with a vitamin K antagonist; however, there are increasing data on the use of DOACs in this population.