Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Triangular opacification of the left lower lobe is increased since the prior exam with new slight blunting of the adjacent left hemidiaphragm on the PA view and opacification of the retrocardiac space on the lateral view . No pleural effusion , pneumothorax , or pulmonary edema . Cardiomegaly persists and is overall unchanged - previously had normal echocardiogram . Mediastinal contours , hila , and pleura are stable .
    OUTPUT:
    
1 . Left lower lobe opacity is new , likely subsegmental atelectasis , but pneumonia can not be excluded in the appropriate clinical setting . 2 . Stable cardiomegaly . Correlate with clinical assessment .