Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A single lead left chest pacer , median sternotomy wires and mediastinal clips are demonstrated . The lungs are clear without focal opacity , pulmonary edema , pleural effusion or pneumothorax . The mediastinal contours are stable over multiple prior studies . There is right atrial enlargement .
    OUTPUT:
    
No acute cardiopulmonary process .