Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post median sternotomy , and tricuspid and mitral valve replacements . Heart size remains moderately enlarged . The mediastinal and hilar contours are unchanged . Mild pulmonary vascular congestion is slightly improved compared to the prior study . Streaky atelectasis is seen in the lung bases . No pleural effusion , focal consolidation or pneumothorax is present . There are mild multilevel degenerative changes noted in the thoracic spine .
    OUTPUT:
    
Mild pulmonary vascular congestion , improved compared to the prior study . Streaky bibasilar atelectasis .