Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are hypoinflated with crowding of vasculature . New retrocardiac opacity may represent atelectasis in combination with superimposed tissue however early developing pneumonia can not be excluded . No pulmonary edema . Stable moderate cardiomegaly . No pleural effusion . Mediastinal contour and hila are unremarkable . A left AICD is unchanged in position since prior examination .
    OUTPUT:
    
1 . New retrocardiac opacity may represent combination of atelectasis and superimposed tissue however early developing pneumonia can not be excluded . 2 . Stable moderate cardiomegaly .