Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Mild cardiomegaly is stable . The mediastinal and hilar contours are normal . Surgical clips and median sternotomy wires are again noted . The lungs are clear without focal opacity , pleural effusion or pneumothorax . There is no free air beneath the right hemidiaphragm .
    OUTPUT:
    
Stable mild cardiomegaly . No acute intrathoracic process .