Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A pacemaker device with four leads appears unchanged . The heart is mild - to - moderately enlarged . The mediastinal and hilar contours appear unchanged . There is similar moderate relative elevation of the right hemidiaphragm with patchy right basilar opacity suggesting minor atelectasis or scarring , not significantly changed . The lungs appear otherwise clear . There is no pleural effusion or pneumothorax . Minimal degenerative change is similar along the lower thoracic spine .
    OUTPUT:
    
No evidence of acute disease .