Cardiac Imaging in Patients After Fontan Palliation: Which Test and When?

Abstract

The Fontan operation represents the final stage of a series of palliative surgical procedures for children born with complex congenital heart disease, where a “usual” biventricular physiology cannot be restored. The palliation results in the direct connection of the systemic venous returns to the pulmonary arterial circulation without an interposed ventricle. In this unique physiology, systemic venous hypertension and intrathoracic pressures changes due to respiratory mechanics play the main role for propelling blood through the pulmonary vasculature. Although the Fontan operation has dramatically improved survival in patients with a single ventricle congenital heart disease, significant morbidity is still a concern. Patients with Fontan physiology are in fact suffering from a multitude of complications mainly due to the increased systemic venous pressure. Consequently, these patients need close clinical and imaging monitoring, where cardiac exams play a key role. In this article, we review the main cardiac imaging modalities available, summarizing their main strengths and limitations in this peculiar setting. The main purpose is to provide a practical approach for all clinicians involved in the care of these patients, even for those less experienced in cardiac imaging.

Role of Cardiovascular Imaging in the Follow-Up of Patients with Fontan Circulation

“…When available, CMR is usually considered the more appropriate choice for further assessment, since it avoids iodate contrast and radiation. It is usually reasonable to perform CMR every 3–5 years, starting from the age of 8, unless an urgent assessment is necessary [ 35 ], and a baseline assessment is recommended at the time of transition from paediatric to ACHD programmes [ 75 ]. This technique can accurately quantify the volume and EF of the dominant ventricle and AV valve regurgitation; it gives accurate information about the patency of the pathways and the aortic arch, and it images collaterals and provides tissue characterisation and feasible 3D reconstructions [ 74 , 75 ].…”

“…Given the advantages of this diagnostic method, CMR is performed routinely in Fontan patients. In most centres, patients undergo yearly echocardiographic studies and a CMR every five years starting from the age of 8, unless an urgent assessment is necessary [ 28 , 35 ].…”