Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post median sternotomy and mitral valve replacement . The heart is moderate enlarged , and the mediastinal and hilar contours are unremarkable . There is no pulmonary edema . Apart from minimal atelectasis at the lung bases , the lungs are clear without focal consolidation . No pleural effusion or pneumothorax is visualized . There are no acute osseous abnormalities demonstrated .
    OUTPUT:
    
No evidence for pneumonia .