Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac silhouette is again noted to be markedly enlarged but unchanged from approximately four hours prior . Again , this is consistent with an underlying pericardial effusion . Further obscuration of the pulmonary vascularity indicates development of mild pulmonary edema . Small bilateral pleural effusions are presumed . No pneumothorax . Retrocardiac opacification is likely atelectasis , although pneumonia can not be excluded .
    OUTPUT:
    
1 . Severe cardiomegaly , unchanged from four hours prior and worrisome for underlying pericardial effusion . 2 . Interval development of mild pulmonary edema from ___ .