Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiographs demonstrate hypoinflated lungs . Persistent small bilateral pleural effusions are noted . Bilateral lower lobe atelectasis again noted . Retrocardiac opacity is most consistent with combination of atelectasis and pleural fluid given elevated left hemidiaphragm however can not exclude overlying infection in the appropriate clinical setting . No focal opacity . No pneumothorax . Heart size mediastinal contour are unremarkable . Multiple clips noted within mediastinum in a patient who is status post coronary artery bypass graft . Diffuse hyperdensity of bilateral lungs is likely artifactual due to over penetration given hypodensities over bilateral subcutaneous tissue . Sternotomy wires are intact and mitral valve replacement is again noted . Limited assessment of upper abdomen is unremarkable and osseous structures are within normal limits .
    OUTPUT:
    
Persistent retrocardiac opacity is most consistent with combination of atelectasis and pleural fluid however can not exclude overlying infection in the appropriate clinical setting . No evidence of pulmonary edema .