Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single AP radiograph of the chest demonstrates an intact median sternotomy wires . Mediastinal clips are seen overlying the left heart border . The lungs are clear with no focal opacity . Scarring at the left lung base . Cardiac , hilar , and mediastinal contours are normal . No pleural abnormality .
    OUTPUT:
    
No acute cardiopulmonary process .