Hi Inanna, I am so sorry for all you and Little Imogen are going through. Im sorry you are still waiting for answers and I am some answers come soon for you and your precious little girl Imogen.
I have been through the waiting, and in many ways still waiting. They were looking into Noonans syndrome with V when she was born, but have since agreed that she doesnt have it. She has been with her pead since being born too, so everytime I go I take a deep breath and hope that he is happy with her progress. For me I am hanging out for the day that my Little V proves all the Dr's wrong.
I truly hope you get some answers soon hun, I know how hard all this waiting is. She too has had her heart u/s done as well as kidney u/s done that all came back ok. The only thing with the heart was a small echogenic focus on her left ventricle, but isnt affecting her heart at all. They explained to me that it is like a feckle on your face but it is on her heart.

Hang in there hun, and know that we are here holding your hand. hugs