Pulmonary & Supravalvar Stenosis

I am a mother of a 3year old kid who was diagnosed with a congenital heart disease (pulmonary and supravalvar stenosis).  She doesn't looked like a kid with heart problem because she looks very healthy and she is very energetic. When she was 8 months old her doctor advise her to undergo a closed heart surgery because at that time only a pulmonary stenosis was seen in the 2dechodiagram.  But before the operation, she underwent the same procedure and was found out that there is also a supravalvar stenosis.   Her doctor postponed the operation and advised us to have our baby undergo 2dechodiagram every 6 months and that if her condition don't improve she will undergo an open-heart surgery.  Her doctor explained that her supravalvar stenosis cannot be corrected through a closed heart surgery.   Is there any other option aside from open-heart surgery??