Fontane surgery is a complex congenital heart disease operation redirecting blood flow from the lower body to the lungs. It is offered to children born with severe heart defects allowing the child to live with just one pumping heart chamber instead of two. This procedure is the last stage operation for kids who are born with congenital heart disease and who cannot be offered a 2-ventricle repair. Although the operation couldn't completely 'fix' the heart most were able to live well into adulthood and have relatively normal lives. But one side effect of this procedure is that those who have