A 66 years old female patient with type 2 DM for 20 year on oral hypoglycemic medications and normal lab and normal Echocardiography 6 month ago present by 2 attack of pulmonary edema which happened early morning one week apart 1st one came with dyspepsia and URTI and vomiting and diarrhea at the same time with dysnea and lasted 2 minutes and subsided spontaneously without medication and 2 nd time happen suddenly and chest auscultation show course crepitation all over chest and after giving lasix iv no response and no urine output and 3 minutes and subsided and patient dysnea disappeared after that pt started to urinate and bring a lot of water. So what is the explanation for pulmonary edema which resolved without medication and why lasix didn't work until late time?