Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: THERE IS PROBABLE BACKGROUND HYPERINFLATION . THE PATIENT IS STATUS POST STERNOTOMY . HEART SIZE IS AT THE UPPER LIMITS OF NORMAL . THERE IS UPPER ZONE REDISTRIBUTION AND MILD VASCULAR PLETHORA , WITHOUT OVERT CHF . FOCAL OPACITY AT THE RIGHT BASE LATERALLY APPEARS TO REPRESENT ARTIFACT DUE TO CONFLUENCE OF RIB AND VASCULAR SHADOWS . THERE IS MINIMAL ATELECTASIS IN THE RIGHT CARDIOPHRENIC REGION , SIMILAR TO ___ . DOUBT ACUTE INFILTRATE . NO GROSS EFFUSION IDENTIFIED .
    OUTPUT:
    
1 . MILD VASCULAR PLETHORA , WITHOUT OTHER EVIDENCE OF CHF . 2 . DOUBT ACUTE INFILTRATE . MILD ATELECTASIS AT THE RIGHT CARDIOPHRENIC REGION IS UNCHANGED COMPARED WITH ___ . 3 . IRREGULAR OPACITY AT THE RIGHT BASE LATERALLY IS COMPATIBLE WITH ARTIFACT DUE TO OVERLAP OF RIB AND VASCULAR SHADOWS .