Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Opacification of the left lung base with associated signs of volume loss , suggests left lower lobe atelectasis . Lateral view demonstrates a superimposed small left pleural effusion . The right lung and left lung apex are well aerated . There is no interstitial pulmonary edema . No pneumothorax is evident . Mediastinal and hilar contours are within normal limits . There is moderate - to - severe cardiomegaly . Dense calcifications of the aortic arch are noted .
    OUTPUT:
    
1 . Left lower lobe atelectasis and small left pleural effusion . 2 . Moderate - to - severe cardiomegaly .