Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest demonstrate no acute cardiopulmonary process . The cardiomediastinal and pulmonary structures are unremarkable . Blunting of the posterior costophrenic angle may represent a tiny pleural effusion , which is unchanged from prior studies . Diaphragms are flattened , compatible with chronic obstructive lung disease . The patient is status post median sternotomy and CABG . There is no pneumothorax or consolidation to suggest infection . There are mild degenerative changes of the thoracic spine . The heart size is top normal .
    OUTPUT:
    
No acute cardiopulmonary process .