Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single portable AP upright chest radiograph demonstrates a heart which is top normal to mildy enlarged in size , similar to prior examination dated ___ . Hilar contour is within normal limits as is mediastinal silhouette . Streaky opacity projecting over the right lung base likely reflects atelectasis . Patient is status post median sternotomy with wires which appear intact . Surgical clips project over the left heart border . There is no overt pulmonary edema . No focal opacity convincing for pneumonia is present . There is no large pleural effusion or pneumothorax .
    OUTPUT:
    
No acute intrathoracic abnormality .