Investigators hope to gain a greater understanding of the hemodynamics of congenital heart disease and their associated operations as they pertain to real-life situations (i.e. upright and non-sedentary, rest and exercise). With this knowledge, investigators would look to optimize the geometry and physiology of the patients, potentially reducing several of the long-term complications found in congenital heart disease patients such as cardiomyopathy, pulmonary hypertension, arrhythmias, thrombosis and heart failure.