Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left - sided dual - chamber pacemaker device is noted with leads terminating in the right atrium and right ventricle , unchanged . Lung volumes are low which accentuate the size of the cardiac silhouette which appears moderately enlarged . Aorta remains tortuous and calcified . There is crowding of the bronchovascular structures with probable mild pulmonary vascular congestion . Patchy opacities in the lung bases likely reflect areas of atelectasis . A small left pleural effusion may be present . No pneumothorax is demonstrated . Multilevel degenerative changes are seen in the thoracic spine .
    OUTPUT:
    
Low lung volumes with patchy bibasilar airspace opacities , likely atelectasis . Possible mild pulmonary vascular congestion and small left pleural effusion .