Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . Previously seen widespread parenchymal opacities have essentially resolved in the interval . There is slight blunting of the posterior left costophrenic angle suggesting a trace pleural effusion versus pleural thickening . Left base atelectasis is seen . The patient is status post median sternotomy and CABG . The cardiac silhouette is top normal . No overt pulmonary edema is seen .
    OUTPUT:
    
Slight blunting the left costophrenic angle may be due to trace pleural effusion or pleural thickening , with overlying atelectasis .