Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is status post median sternotomy and CABG . Severe enlargement of the cardiac silhouette process . The aorta remains unfolded . Mild pulmonary vascular congestion is similar to that seen on the prior study . No pleural effusion or pneumothorax is identified . Patchy atelectasis is noted in the lung bases . No pneumothorax is present . Moderate degenerative changes are noted in the thoracic spine .
    OUTPUT:
    
Mild pulmonary vascular congestion and bibasilar atelectasis .