Is it worth getting the bnp test if your echocardiogram and chest ct, lung function test were oaky but still have shortness of breath at times?

Maybe...: If all pulmonary tests were normal, and Echo shows normal pumping function, have them check the valves very well and also check for Diastolic Dysfunction. That is when the heart is a little "stiff" and doesn't relax very well. BNP levels can go up a little bit with Diastolic Dysfunction, though not typically as high as in Systolic Dysfunction (weak heart).