Failure of Fontan Type Circulation

The goal of this observational clinical study look at the safety and effectiveness of the Occlutech Atrial Flow Regulator in the treatment of patients with failing Fontan circulation. This study will consist of a case series of congenital patients with Fontan failure who have been treated with an Occlutech AFR under the FDA's Expanded Access process. The scope of this study is to gain clinical experience on the Occlutech AFR in Fontan failure patients. Cases in this study will be evaluated to evaluate the safety and effectiveness of the device. The objective of this study is to evaluate the Occlutech AFR with respect to device safety and shunt patency at 1 year. Shunt patency defined by persistent right to left shunt assessed by echocardiography at 1-year post-procedure.