Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours appear unchanged including evidence for prior coronary artery bypass graft surgery and mild cardiomegaly . Dishiscence of the third highest sternal wire appears unchanged . Small pleural effusions are difficult to exclude . In addition to mild vascular congestion , which appears unchanged , there are patchy increased opacities at the lung bases . Pneumonia can not be excluded although these may be seen with volume loss and atelectasis . Lung volumes are low .
    OUTPUT:
    
1 . Findings suggesting mild vascular congestion . 2 . Patchy opacities at both lung bases , although greater on the left than right . Although pneumonia is not excluded by this examination , findings could also be seen with atelectasis .