Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral chest radiograph demonstrates median sternotomy wires which appear intact . A prosthetic mitral valve is noted . There is a small to moderate right pleural effusion decreased in size relative to prior study . Several opacities project over the right lower lung zone , likely artifactual and superimposed osseous structures . Streaky opacity within the left upper lobe is unchanged . Blunting of the left costophrenic angle likely reflect small pleural effusion . Cardiomediastinal silhouette is stable . No evidence of pulmonary edema . There is no pneumothorax .
    OUTPUT:
    
Small to moderate right pleural effusion decreased in size relative to prior study . Small left pleural effusion . No acute intrathoracic abnormality .