Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A left - sided pacemaker defibrillator is seen with multiple leads in appropriate position . The patient is status post median sternotomy . The heart is normal in size . Cardiomediastinal silhouette and hilar contours are within normal limits . Subtle opacities at the right base are most consistent with atelectasis . There is no large pleural effusion or pneumothorax identified .
    OUTPUT:
    
Subtle opacities at the right base are most consistent with atelectasis .