Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single portable upright frontal image of the chest . Pacemaker , leads , median sternotomy wires , and mediastinal surgical clips are stable . The lung volumes are low with associated bronchovascular crowding . The lungs are clear . There is no large pleural effusion or pneumothorax . The cardiomediastinal silhouette is unchanged from prior exam .
    OUTPUT:
    
No acute cardiopulmonary process .