Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Evaluation of the lung parenchyma is somewhat limited due to dense overlying soft tissues . Within these limitations , there is dense retrocardiac opacification , seen best on the lateral view , which may be due to atelectasis related to stable moderate - to - severe cardiomegaly . However , pneumonia is a consideration in the appropriate clinical setting . Cardiomediastinal and hilar contours are unchanged . No pleural effusion is identified .
    OUTPUT:
    
Dense retrocardiac opacification could be consistent with pneumonia in the appropriate clinical setting , though atelectasis related to stable cardiomegaly is also likely .