Advances in Diagnostic and Interventional Catheterization in Adults with Fontan Circulation

Abstract

Over the past five decades, the Fontan procedure has been developed to improve the life expectancy of patients with congenital heart defects characterized by a functionally single ventricle. The Fontan circulation aims at redirecting systemic venous return to the pulmonary circulation in the absence of an impelling subpulmonary ventricle, which makes this physiology quite fragile and leads to several long-term complications. Despite the importance of hemodynamic assessment through cardiac catheterization in the management and follow-up of these patients, a thorough understanding of the ultimate functioning of this type of circulation is lacking, and the interpretation of the hemodynamic data is often complex. In recent years, new tools such as combined catheterization with cardiopulmonary exercise testing have been incorporated to improve the understanding of the hemodynamic profile of these patients. Furthermore, extensive percutaneous treatment options have been developed, addressing issues ranging from obstructive problems in Fontan pathway and acquired shunts through compensatory collaterals to the percutaneous treatment of lymphatic circulation disorders and transcatheter edge-to-edge repair of atrioventricular valves. The aim of this review is to detail the various tools used in cardiac catheterization for patients with Fontan circulation, analyze different percutaneous treatment strategies, and discuss the latest advancements in this field.

Keywords: Fontan circulation; catheterization; congenital heart disease; hemodynamic assessment; percutaneous interventions; single ventricle.

Figure 1

Long-term Fontan complications. AV: Atrioventricular, FALD: Fontan-associated liver disease, HF: Heart failure. BioRender.com has been used for the creation of this figure (Agreement number: RI275JMOWR).

Figure 2

Fontan gradient between the superior and inferior vena cava unmasking an obstructive gradient in the Fontan conduit during exercise. (A) SVC-IVC gradient at rest of 1 mmHg. (B) SVC-IVC gradient during exercise of 9 mmHg. LV: single ventricle, SVC: superior vena cava, IVC: inferior vena cava.

Figure 3

Contrast angiographic studies: (A) Systemic to pulmonary venous collaterals (SPVCs); (B) Major aortopulmonary collateral arteries (MAPCAs); (C) Macrovascular pulmonary arteriovenous malformation (PAVM).

Figure 4

Percutaneous treatment of Fontan pathway obstructions with stent angioplasty on (A,B) an obstructed extracardiac Fontan conduit, on (C,D) an atriopulmonary anastomosis in classic Fontan, and on (E,F) a complete occlusion of the left pulmonary branch artery. The arrows in each figure indicate the point of obstruction or occlusion.

Figure 5

Percutaneous intervention in cyanotic patients due to right-to-left shunt: (A,B) Fenestration closure; (C,D) Veno-venous shunt closure from a persistent left superior vena cava (LSVC) to the coronary sinus (CS). The arrows in each figure indicate the shunt and its closure with an occlusion device.

Figure 6

Acute pulmonary thromboembolism: (A) angiographic image of a thrombotic occlusion in the main branch of the left lower lobar artery (see arrow); (B) thrombus extracted after percutaneous aspiration thrombectomy.

Figure 7

Double inlet left ventricle, initially palliated with a Damus-Kaye-Stansel (DKS) procedure and subsequently with a Fontan procedure, presenting an invasive gradient of 18 mmHg in the thoracic aorta. (A) Angiographic image of the neoaorta in a patient with DKS with an associated aortic coarctation (AC) marked by an arrow; (B) Placement of a stent at the level of the coarctation (arrow); (C) Percutaneous repair of the AC after stent deployment (arrow).