Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post coronary artery bypass graft surgery . The cardiac , mediastinal and hilar contours appear unchanged . There is no pleural effusion or pneumothorax . Mild background interstitial abnormality appears unchanged without superposition of any discrete focal opacity . Findings are very similar to the prior examination .
    OUTPUT:
    
Mild interstitial abnormality suggesting pulmonary vascular congestion , but little if at all changed from baseline .