Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP semi-upright view of the chest is reviewed and compared to the prior study . An aortic core valve projects over the heart and a transvenous right internal jugular pacer follows the expected course and is unchanged in position . Interstitial abnormality is unchanged since ___ , but increased since ___ , probably due to edema , exaggerated by low post operatived lung volumes . There is no significant pleural effusion or pneumothorax . The cardiomediastinal silhouette , reflecting mild cardiomegaly , are unchanged . Elevation of the left hemidiaphragm is chronic .
    OUTPUT:
    
1 . Mild interstitial edema stable since ___ , increased since ___ .