As I was reading the comments friends have left over the last few days, I noticed that I never really explained what Brett's heart defect was.
So, I'll give it my best shot. Please keep in mind that I am not a doctor and I've pieced together information we have received from several doctor visits since his birth.
Brett was diagnosed with a Tetralogy of Fallot. This is a series of four structural defects including: a ventricular septal defect (VSD), an overriding aorta, a hypertrophic right ventricle and pulmonary stenosis. All of this fancy talk just means that there is a hole between the lower chambers of the heart and the aorta is incorrectly growing from both ventricles, rather than exclusively from the left. In addition, the pulmonary valve, which connects the heart to the lungs, is smaller and obstructs the blood flow to the lungs. Lastly, the right ventricle works extra hard and the muscle surrounding the lower right chamber becomes thickened.
We knew prior to Brett's surgery that he did not have the overriding aorta. However, he had an additional hole between the upper chambers of his heart (ASD). Entering the surgery we anticipated that both the ASD and VSD would be closed. In addition, we expected that the pulmonary valve would be enlarged and that a portion of the right ventricle would be cut away to allow blood to flow to the lungs more easily. After surgery we were told that only the ASD and VSD needed repair.
Again, I will reiterate that I am not a doctor and I may not have all the facts straight.