Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left - sided dual - chamber pacemaker appear unchanged with the leads in right atrium and right ventricle . The lungs are well expanded and clear . No pleural abnormality is seen . The hilar and mediastinal contours are normal . The heart size is top normal .
    OUTPUT:
    
Left - sided dual - chamber pacemaker with leads in standard position .