<s>[INST] I have a question I have been not well for three years it all started when I lost 30 pounds now I have cysts on my lungs, liver, breast and ovarie. I have seen several lung and heart doctors but nobody knows what is wrong any ideas what could cause all this and make me feel so bad. I had a mammogram because my left breast has a burning sensation they found nothing, I had a pet scan in 2007 they found nothing, I had a cardiopulmonary stress test and all they found was low mvv of 73% and subtle gas exchange abnormalities but nobody will say what this means if anything. Please any advice is greatly appreciated [/INST] Hello! Welcome to Chat Doctor !  MVV stands for maximum voluntary ventilation. It is simply a measure of your maximum breathing capacity. A reduced MVV implies that there is a limitation on your respiratory system. That could be in the lungs or outside the lungs. The finding itself does not specify where the problem is however, just that there could be a problem. If you have multiple cysts on your lungs, this could be what led to this slight abnormality. This MVV reduction by itself should not cause you any alarm, however.  I hope this clarifies your concerns. Thank you for the query. Take care  </s>