hypoplastic left heart syndrome, and with postoperative chylothorax, many affected individuals have no obvious risk factors.192 The onset is often insidious, but once PLE is established, patients with this condition are among the most chronically debilitated of all those with congenital heart disease Although it is well understood that abnormal lymphatic connections to the intestine are responsible for the loss of lymphatic fluid that occurs with PLE, there are likely other contributing factors to this disease Endoscopy often demonstrates an inflammatory pattern similar to that observed in children with inflammatory bowel disease Like inflammatory bowel disease, there are cases of PLE that can be controlled through the use of corticosteroids.202 Oral controlled-release budesonide is a steroid formulated to target its antiinflammatory properties to the distal small intestine Budesonide has the added advantage of first pass hepatic metabolism, theoretically leading to a lower degree of systemic absorption than with other corticosteroids Unfortunately, some cases of PLE are steroid resistant In older adolescents and young adults, controlled release budesonide has not been as effective a treatment.203 Although the response to steroids in younger children suggests an inflammatory component of the disease, the absence of a response in adolescents and young adults suggests that inflammation may play less of a role in older patients Although the underlying abnormal connections between the lymphatic vessels and the intestine are present in both age groups, the differential response to treatment suggests that the breakdown of the integrity of the intestinal mucosa may have more of a relationship to inflammation in younger patients In any age group, the treatment strategy for PLE begins with optimizing the overall Fontan physiology Diuretics may be helpful by decompressing the lymphatic system and may also treat some of the symptoms associated with PLE.186,198 Pulmonary vasodilators may be useful adjuncts because the reduction in pulmonary vascular resistance leads to a drop in CVP and therefore a reduction in intralymphatic pressure Other potential therapies have been reported and include the administration of heparin and even treatment with lowdose dopamine infusion.204,205 Unfortunately, although medical treatment has led to improved outcomes, the burden of morbidity and mortality remains substantial As in the case of plastic bronchitis, the emergence of lymphatic imaging and intervention has the potential to alter the strategy for the treatment of those with PLE.187,188 By accessing and occluding the abnormal lymphatic connections from the hepatic lymphatics to the intestines, one could substantially alter the rate of loss of lymphatic fluid However, although promising, lymphatic intervention for PLE is not as successful as it has been for plastic bronchitis Nevertheless, recent reports of lymphatic intervention suggest that with further technical refinement, there is the potential to fundamentally alter the trajectory of those who develop this feared complication Peripheral Vascular Disease Increased arterial stiffness and small arterial lumen diameter have been reported in Fontan patients, the latter presumably a response to a chronic reduction in cardiac output.53,206–208 These arterial abnormalities, in combination with those of lymphatic drainage described earlier and chronic venous insufficiency, manifest in the lower extremities as varicose veins, edema, and, in serious cases, chronic ulceration These lower extremity problems occur in approximately 20% of Fontan patients older than 18 years and are more common in those who have had multiple cardiac catheterization procedures or central venous catheters via the femoral veins They are also associated with deep venous thrombosis and as such may predispose to pulmonary and systemic embolism.209 Neurocognitive and Psychosocial Function The diagnosis of a life-threatening illness during a child's formative years can have far-reaching effects that ripple through the family and across a lifetime Children following the Fontan pathway experience profound physical, emotional, behavioral, neurodevelopmental, and social challenges in the early years of life, and these challenges have the potential for lifelong consequences, particularly in relation to future health, well-being, and QOL Quality of Life The World Health Organization defines quality of life as a dynamic, multidimensional concept, unique to each individual's perception of his or her position in life and his or her physical health, psychological well-being, level of independence, relationships, personal beliefs and values, and environmental context.210 In the context of functionally univentricular congenital heart disease, stressors associated with diagnosis and treatment, the uncertainty of progressive functional limitations, and the possibility of heart failure, heart transplantation, arrhythmias, and sudden death may compromise QOL Overall, the majority of published studies report lower QOL for children and adults with a Fontan circulation compared with normative data, age-matched controls, or healthy siblings211,212; however, a small number of studies report QOL similar to the general population.213,214 Although some studies have demonstrated an association between lower QOL and greater complexity of cardiac abnormality, daily medication use, greater length of hospital stay, and greater number of medical interventions,215,216 most research has found that social and psychological constructs, such as greater psychological stress, fewer social supports, and lower family socioeconomic status, play a more influential role in determining QOL.215–219 Consensus on the role of these risk factors in the Fontan population has not been established Neurocognitive Outcomes From a neurocognitive perspective, it is well established that children with