Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were provided . Midline sternotomy wires and mediastinal clips are again noted . Minimal density at the left lung base is more compatible with atelectasis . No convincing signs of pneumonia . No free air below the right hemidiaphragm . The aorta is unfolded . The heart size appears normal . No pneumothorax . No signs of pulmonary edema . Bony structures appear intact . A vascular stent is partially visualized in the upper abdomen .
    OUTPUT:
    
Mild left basal atelectasis . No convincing signs of pneumonia .