Usefulness of 4D-Flow MRI in Mapping Flow Distribution Through Failing Fontan Circulation Prior to Cardiac Intervention.

We report a case of a 23-year-old male with failing Fontan circulation who was taken to the catheterization lab to better evaluate the Fontan circulation and hemodynamics. Catheterization revealed arteriovenous malformations exclusively present in the right lung leading to the consideration of placing stents to direct the inferior vena cava flow through the Fontan circuit to the right pulmonary artery (RPA), thus increasing the RPA concentration of the hepatic factor. However, comprehensive 4D-Flow MRI analyses indicated sufficient distribution of the hepatic flow between branch pulmonary arteries, and consequently no further invasive intervention to redirect hepatic flow was performed.