Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are well inflated . The left lung demonstrates some linear basilar opacities suggesting discoid atelectasis . An ill - defined opacity in the right lung base is not significantly changed compared with prior exam on ___ , and might represent an area of atelectasis or scarring . This area of ill - defined opacity was also present on ___ . Otherwise , the cardiomediastinal and hilar contours are unchanged . There is mild cardiomegaly . A moderate - sized hiatal hernia is again seen . There is no pleural effusion or pneumothorax . Sternotomy wires are intact . A prosthetic aortic valve is unchanged in position . Dual lead pacemaker is noted in the left chest with leads ending in expected position in the right atrium and ventricle .
    OUTPUT:
    
No evidence of acute cardiopulmonary process .