Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is a single - lead pacemaker device terminating in the right ventricle . The heart is mildly enlarged . The mediastinal and hilar contours are unremarkable . Streaky left basilar opacities suggest slight atelectasis . Otherwise , the lung bases appear clear . There are no pleural effusions or pneumothorax . The course of the right lateral seventh rib is anomalous with a smooth and slight angulation suggesting remote prior fracture . Mild degenerative changes are noted along the thoracolumbar junction .
    OUTPUT:
    
No evidence of acute disease .