Endothelial dysfunction in single ventricle physiology and the Fontan circulation - What lies ahead

Endothelial dysfunction is characterized by a vasoconstricted, pro-coagulative, and pro-inflammatory phenotype and is known to play a role in several chronic non-communicable diseases. Several biophysical and biochemical markers have been developed to assess endothelial function clinically. Its relevance in individuals born with single-ventricle congenital heart disease (SV-CHD) is increasingly recognized. Endothelial dysfunction has been observed in all stages of palliation in SV-CHD patients. Several mechanisms possibly contribute, including genetic factors, hypoxia, loss of pulsatility of blood flow, neurohormonal and sympathetic overactivation, and oxidative stress. Clinically, it possibly contributes to impaired pulmonary flow, exercise limitation, thromboembolisms, liver dysfunction, and adverse pregnancy outcomes. Based on this information, several therapeutic targets have been proposed such as early surgical and exercise interventions, pulmonary vasodilators, and other common pharmacological agents. However, much remains unknown and future studies must unravel the relationship of endothelial dysfunction with this complex patient group, ultimately improving their clinical care.