Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest . Left base opacity appears increased since ___ , consistent with a moderate size pleural effusion with underlying atelectasis or infection . Pulmonary vascular markings are prominent , consistent with vascular congestion . The right lung appears otherwise clear . No pneumothorax . Heart size is enlarged but difficult to evaluate given the left base opacity . Mediastinal contours are otherwise stable .
    OUTPUT:
    
1 . Increased left base opacity since the prior exam , consistent with a moderate left pleural effusion with underlying infection and / or atelectasis . 2 . Mild pulmonary vascular congestion .