Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: No focal opacity to suggest pneumonia is seen . No pleural effusion , pulmonary edema or pneumothorax is present . There is atelectasis at the left base . The patient is status post median sternotomy and CABG with unchanged pleural thickening at the left apex .
    OUTPUT:
    
No acute intrathoracic process .