Yes there are high pressure and all sorts of veins growing in the chest and stomach.They can't do a heart transplant because of the pressure is so high that he will bleed to death. They also tried to go in and block of some of those veins but there are to many.His liver is swollen from the pressure and bleeding in the bowels.
Dear Hughes Baby,
I would need to evaluate your nephew further before saying what is happening here. However, I can give you some background. The Fontan is typically the third in a series of surgeries for children born with a single ventricle instead of the normal two. It relies on flow to go directly from the large veins of the body returning blood to the heart into the pulmonary arteries without an intervening ventricle pumping it in. This means that there needs to be an unobstructed pathway with low pressure to get blood into the lungs. What you are describing is concerning to me that there may be either some significant obstruction or high pulmonary artery pressure, or both, that is causing blood to back up and cause the findings he is experiencing. However, it could also be occuring if his heart is not pumping well. This is a seroius problem that requires an experienced team of pediatric cardiologists and cardiac surgeons.