Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . The heart is moderately enlarged . Increased retrocardiac opacity likely secondary to atelectasis . The left hemidiaphragm is partially obscured secondary to a small left pleural effusion . No focal consolidation or pulmonary edema . No pneumothorax .
    OUTPUT:
    
No evidence of pneumonia . Small left pleural effusion atelectasis .