Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP upright view of the chest provided . Midline sternotomy wires are again noted . The heart is stably enlarged with an unfolded thoracic aorta again noted . Tiny clips in the mediastinum are again seen . The lungs are clear without focal consolidation , effusion or pneumothorax . Lung volumes are somewhat low . No definite signs of edema . Bony structures are intact . No free air below the right hemidiaphragm .
    OUTPUT:
    
Stable cardiomegaly . No signs of pneumonia or pulmonary edema .