Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left - sided dual - chamber pacemaker device is re - demonstrated with leads in unchanged positions . Low lung volumes result in accentuation of the cardiac silhouette size which is borderline enlarged . The aorta remains unfolded . Pulmonary vasculature is normal . There is mild atelectasis within the medial right lung base without definite focal consolidation , pleural effusion or pneumothorax . No acute osseous abnormality is visualized .
    OUTPUT:
    
Low lung volumes with mild right basilar atelectasis .