Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post median sternotomy and CABG . Moderate cardiomegaly is re - demonstrated . Thoracic aorta remains tortuous and diffusely calcified . The mediastinal and hilar contours are unchanged . Streaky and linear atelectasis is noted in both lung bases , and the lung volumes are low . There is crowding of the bronchovascular structures without overt pulmonary edema . No pneumothorax is demonstrated . Previously demonstrated small bilateral pleural effusions have improved , with minimal residual bilateral pleural effusions , larger on the right . No acute osseous abnormalities seen .
    OUTPUT:
    
Low lung volumes with bibasilar atelectasis . Minimal bilateral residual pleural effusions .