Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP portable upright chest radiograph was provided . Overlying EKG leads limit the evaluation . Also noted , low lung volumes limit evaluation . Bronchovascular crowding is noted without convincing sign of pneumonia or CHF . Mitral annular calcification again noted . The heart is within normal limits of size . Mediastinal contour is unremarkable . Bony structures are intact .
    OUTPUT:
    
Limited , negative for acute intrathoracic process .