Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal lateral views of the chest demonstrate left pectoral cardiac pacer with leads terminating in the right atrium and right ventricle . There is evidence of prior CABG . Median sternotomy wires are intact . Massive cardiomegaly is similar as before . Low lung volumes are unchanged . There is interval improvement of previously mild interstitial edema . Streaky retrocardiac opacities may be a combination of a chronic changes and subsegmental atelectasis . There is likely a small left pleural effusion .
    OUTPUT:
    
1 . Interval improved pulmonary edema . 2 . Mildly increased small left pleural effusion and atelectasis admixed with chronic changes in the left lung base .