Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Monitoring and support devices are in standard position and unchanged from the prior examination . Again seen is a large retrocardiac opacity which obscures the left heart border and likely represents left lower lobe collapse and moderate left pleural effusion . Additionally , there is a new leftward mediastinal shift . The right lung is clear . The cardiomediastinal and hilar contours are unchanged . There is no evidence of pneumothorax .
    OUTPUT:
    
Left lower lobe collapse and moderate left pleural effusion with leftward mediastinal shift . Findings communicated to Dr . ___ by telephone at 3 : 22 on ___ by Dr . ___ .