Hi, I Have An Enlarged Pulmonary Artery (40 Mm, That

Hi, I have an enlarged pulmonary artery (40 mm, that was 37 mm in a prior CT chest and abdominal scan done a month prior) and an enlarged right ventricle. I just had a right and left cath done and pressure is normal (not PAH) and no heart or plaque problems. Also had an echo and stress test, and a cardiac CT and all were normal, except for the pulmonary artery size. I also have a raised right hemidiaphragm for several years that was operated on and lowered about 12 years ago, but it is elevated again. (I have had many abdominal surgeries.) I don't know if this is related, but seems like an odd coincidence. The only symptom is getting easily out of breath when attempting to exercise, with some right chest or abdominal pain. BTW, no sleep apnea. What could the enlarged pulmonary cause be? Should I be concerned? Does it require more testing? What further testing should be done? Thank you.