Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Two views of the chest were obtained . The lungs are well expanded and clear with linear left mid - lung atelectasis . There is no pleural effusion or pneumothorax . The heart remains enlarged with postsurgical changes . The aortic contour is normal and unchanged from the prior study . Small hiatal hernia may be present .
    OUTPUT:
    
No acute intrathoracic process .