Hi I have had results of my lung function. Spirometry just within normal limits but corrected CO is reduced at 74%. I have rhf also?

Part of lung lost? The DLCO/Va reflects your lung volume. If it is reduced , that usually means that either part of your lung was removed or something is blocking a part of your lung. You need to be checked out for pulmonary fibrosis as well. Do you keep a budgie at your home?