Long Term Consequences of the Fontan Procedure and How to Manage Them

Abstract

In 1971, Fontan and Baudet described a surgical technique for successful palliation of patients with tricuspid atresia. Subsequently, this technique has been applied to treat most forms of functional single ventricles and has become the current standard of care for long-term palliation of all patients with single ventricle congenital heart disease. Since 1971, the Fontan procedure has undergone several variations. These patients require lifelong management including a thorough knowledge of their anatomic substrate, hemodynamic status, management of rhythm and ventricular function along with multi organ evaluation. As these patients enter middle age, there is increasing awareness regarding the long-term complications and mortality. This review highlights the long-term outcomes of the Fontan procedure and management of late sequelae.

Single-Ventricle Physiology

“…It is the most common type seen in children and it presents with consistent signs and symptoms of heart failure with reduced EF, such as pulmonary edema, hepatic congestion, and ascites. 7,17 This closely resembles systolic heart failure in patients with two ventricles. 17 Type 2 heart failure in Fontan patients, known as Fontan failure with preserved ejection fraction, presents with a preserved ejection fraction, with signs and symptoms of pulmonary venous congestion and hepatic congestion, with elevated venous pressures.…”

“…The survival rates of hypoplastic left heart syndrome had significantly worse outcomes, with survival ranging from 72% to 85% at 10 years. 7…”

“…Heart failure in people who have had the Fontan procedure is fundamentally different from heart failure in patients with two ventricles. 7,17 While heart failure in people with two ventricles helps provide a framework to understand heart failure in the single ventricle, it is essential that we understand where and how the two types of patient diverge.…”

“…There are four types of heart failure described in people who have had the Fontan procedure and in each case the circulation is no longer able to meet the metabolic demands of the body. 7 Type 1 heart failure in Fontan patients is also called Fontan failure with reduced ejection fraction. It is the most common type seen in children and it presents with consistent signs and symptoms of heart failure with reduced EF, such as pulmonary edema, hepatic congestion, and ascites.…”

“…They are largely dependent on skeletal muscle pump and ventilation mechanics during exercise to increase their venous return and stroke volume. 7,8 It has been demonstrated that in adults with Fontan circulation, nearly 30% of their venous flow through the pulmonary artery is dependent on respiration, whereas in patients with two ventricles this number is closer to 15%. 8,10 Due to the increase in their venous vasculature resistance, people with Fontan circulation also have a diminished venous capacitance.…”