Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Right - sided Port - A - Cath tip terminates at the junction of the SVC and right atrium . Patient is status post median sternotomy and aortic valve replacement . Lung volumes are low with mild enlargement of the cardiac silhouette , unchanged . Mediastinal and hilar contours are similar . There is mild pulmonary edema , slightly improved in the interval . Patchy opacities in the lung bases may reflect areas of atelectasis , but infection particularly in the left lung base can not be completely excluded . No pleural effusion or pneumothorax is demonstrated . Elevation of the left hemidiaphragm is again noted . No acute osseous abnormality is visualized .
    OUTPUT:
    
Slight improvement in mild pulmonary edema . Patchy opacities in the lung bases may reflect atelectasis , but infection particularly in the left lung base can not be completely excluded .