Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is status post median sternotomy and CABG . The heart size is normal . The mediastinal and hilar contours are unchanged . Low lung volumes are present . There is crowding of bronchovascular structures with mild pulmonary vascular congestion . New small right pleural effusion appears decreased in size compared to the prior study . Patchy opacities in the lung bases , more pronounced on the right , are not substantially changed in the interval , and likely reflect areas of atelectasis . Infection or aspiration in the right lung base however can not be completely excluded . No pneumothorax is detected . Radiopaque focus projects over the right dome of the liver , perhaps a coil , unchanged .
    OUTPUT:
    
Small right pleural effusion , decreased in size from the prior study , with mild pulmonary vascular congestion . Patchy opacities in the lung bases may reflect atelectasis , but aspiration or infection can not be completely excluded in the right lung base .