Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low with secondary crowding of the bronchovascular markings . There is however superimposed pulmonary edema which may have progressed since prior although changes could in part be to lower lung volumes . Enlargement of the cardiac silhouette is also noted , again not significantly changed . More dense left basilar opacity , particularly on the frontal view could be combination of atelectasis noting that infection is difficult to exclude . .
    OUTPUT:
    
Cardiomegaly and pulmonary edema which may have progressed since prior although some changes may be accounted for by lower lung volumes on the current exam . Left basilar opacity , potentially atelectasis noting that infection would also be possible .