Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left - sided dual lead pacemaker in place . Lung volumes are low . Bibasilar subsegmental atelectasis is present . There is no pneumothorax . Improved but persistently prominent interstitial markings may be due to improving pulmonary edema . Lateral left basilar airspace opacity may either be due to atelectasis or infection .
    OUTPUT:
    
Improving pulmonary edema or infection . Lateral left basilar airspace opacity may be due to atelectasis or infection .