Very odd...I don't know anything about the organs enlarging but find this strange.
Has your python ate since you got it? How long have you had it now? Will the vet benefit by saying it has a heart issue? I wouldn't do anything...if the animal has a heart problem that is a genetic thing and cannot be controlled in my opinion I would just let it live a happy life?
Hope he/she is just fine and has eaten for you, if it doesn't seem sick I would not be concerned.