Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views of the chest provided . Midline sternotomy wires and prosthetic cardiac valve again noted . Lung volumes are somewhat low . Mild cardiomegaly is again noted . There is no large consolidation , effusion or pneumothorax . No overt edema . Mediastinal contour is prominent likely in part due to rotation and unfolded thoracic aorta . Bony structures appear intact .
    OUTPUT:
    
No acute findings .