Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . Patient is status post median sternotomy and CABG . There are low lung volumes . Mild bibasilar atelectasis is seen without definite focal consolidation . There is slight blunting of the right costophrenic angle , and trace pleural effusion is not excluded . The cardiac and mediastinal silhouettes are stable . There may be minimal pulmonary vascular congestion . There is an old fracture of the right - sided posterolateral sixth rib .
    OUTPUT:
    
Low lung volumes with possible minimal vascular congestion . Bibasilar atelectasis without focal consolidation .