Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared to the prior study the pulmonary edema and cardiomegaly has improved with persistent mild enlargement of the cardiac silhouette . Lung volumes are low and there is a linear opacity in the left lower lobe likely reflecting atelectasis . No pneumothorax . No free air under the diaphragms .
    OUTPUT:
    
Low lung volumes with linear left lower lobe atelectasis .