Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is status post median sternotomy and CABG . There is mild enlargement of the cardiac silhouette which is unchanged . Mediastinal and hilar contours are unchanged . There is no pulmonary vascular congestion . A moderate left pleural effusion appears similar in size compared to the previous exam . There is continued opacification of the left lung base , which could reflect compressive atelectasis . Right lung is clear . No pneumothorax is identified . Multilevel degenerative changes are noted in the thoracolumbar spine with loss of height of a vertebral body at the thoracolumbar junction which is unchanged .
    OUTPUT:
    
Moderate left pleural effusion , similar compared to the previous exam with persistent left basilar compressive atelectasis . Infection is not completely excluded .