Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest demonstrate prominent cardiac silhouette and mildly tortuous thoracic aorta , with arch calcifications . The lungs appear hyperexpanded with perihilar retractile changes and diaphragmatic flattening , configuration compatible with emphysema . There is no pneumothorax , vascular congestion , or large pleural effusion . Plate - like atelectasis is seen in the left base . There may have been prior healed fracture of the posterolateral left second rib .
    OUTPUT:
    
1 . Plate - like atelectasis in the left base . 2 . No definite acute cardiopulmonary process .