Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Median sternotomy wires and mediastinal clips are again noted . Lung volumes are low accentuating the cardiac silhouette . Moderate cardiomegaly is likely unchanged . Hilar contours are unremarkable . There is mild retrocardiac atelectasis . Lungs are otherwise clear . Pleural surfaces are clear without effusion or pneumothorax . Chronic deformity of the proximal left humerus is again noted .
    OUTPUT:
    
No acute cardiopulmonary abnormality .