Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP portable upright chest radiograph obtained . Midline sternotomy wires and mediastinal clips are noted . The heart is moderately enlarged . The lung volumes are low without clear sign of pulmonary edema or pneumonia . A tiny left pleural effusion is noted . The imaged osseous structures are intact . Mediastinal contour is normal .
    OUTPUT:
    
Moderate cardiomegaly with small left pleural effusion .