Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is moderately enlarged . The hilar and mediastinal contours are within normal limits . The aorta is heavily calcified and tortuous . The patient is post median sternotomy . There is no pneumothorax or pleural effusion . Bibasilar linear opacities likely denote atelectasis . There is a linear left middle zone opacity which may represent scarring or atelectasis .
    OUTPUT:
    
No acute intrathoracic process . Moderate cardiomegaly .