Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The previously seen right IJ line has been removed . No pneumothorax is detected . Again seen is a left - sided single lead pacemaker ( transvenous right ventricular pacer defibrillator ) with lead over the right ventricle . Lordotic positioning . Again seen are low inspiratory volumes . Stable prominence of the cardiomediastinal silhouette , with fixation hardware again noted -- this appearance is likely accentuated by AP technique , low volumes , lordotic positioning . There is increased retrocardiac density , consistent with left lower lobe collapse and / or consolidation , overall similar to the prior study . Patchy right perihilar opacity is are also similar , possibly slightly more pronounced . Equivocal vascular engorgement . No gross effusion .
    OUTPUT:
    
1 . Overall , the appearance is quite similar to the ___ chest x-ray . 2 . CHF difficult to assess , but probably not worse compared with the prior film . No gross effusions , though small effusions could very well be present . 3 . Left lower lobe collapse and / or pneumonic consolidation is grossly unchanged . 4 . Opacity seen in the right perihilar region is of uncertain etiology --___ atelectasis , but an infectious infiltrate can not be entirely excluded . This appearance is also similar , possibly minimally worse , compared to the prior study .