Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: On the frontal , the lungs are clear . However , on the lateral view there is increased opacity projecting in the subcarinal region , new since previous exam . This persists on multiple lateral views . While this may be due to superimposed shadows from hilar vasculature , left atrium and tortuous aorta , nonurgent chest CT is suggested to further evaluate . There is no effusion or pneumothorax . Mild cardiomegaly is noted as well as a prosthetic aortic valve . Median sternotomy wires are noted . No acute osseous abnormalities identified .
    OUTPUT:
    
No acute cardiopulmonary process . Mild cardiomegaly . Increased subcarinal opacity on the lateral view could potentially be superimposed shadows however is new since prior and dedicated nonemergent chest CT is suggested to further characterize