Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post median sternotomy and valve replacement . Mild cardiomegaly is present . Right - sided pacemaker device is noted with leads terminating in the region of the right atrium and right ventricle . Widening of the superior mediastinal contour is noted , which could be due to low lung volumes and the presence of mediastinal fat . There is crowding of bronchovascular structures with mild pulmonary vascular congestion noted . Patchy retrocardiac opacity likely reflects atelectasis . No large pleural effusion or pneumothorax is seen . There are no displaced fractures identified .
    OUTPUT:
    
Mild pulmonary vascular congestion with patchy retrocardiac opacity likely reflecting atelectasis . Widening of the superior mediastinal contour may be related to low lung volumes ; comparison with prior radiographs would be helpful , if there is continued concern for acute traumatic injury within the chest , a chest CT is recommended .