Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Sternotomy wires are intact . Coronary artery bypass graft stent an several coronary artery stents are again noted . Moderate enlarged cardiac contour is similar to before . There is no consolidation , pleural effusion , or pneumothorax . There is subsegmental atelectasis at the mid lung fields bilaterally .
    OUTPUT:
    
No radiographic evidence of pneumonia . Subsegmental atelectasis .