Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is improved aeration of the left lower lobe with decreased left pleural effusion and left lower lobe atelectasis . Right lower lobe opacity is unchanged . Stable mild cardiomegaly . Mediastinal contour and hila are otherwise unremarkable . Intact median sternotomy wires and mitral valve prosthesis again noted . A right IJ CVL tip is in the lower right atrium .
    OUTPUT:
    
1 . Improved aeration of left lower lobe with decreased left pleural effusion and left lower lobe atelectasis . 2 . Stable right lower lobe opacity most consistent with atelectasis . 3 . Stable mild cardiomegaly . 4 . Right IJ CVL tip in the lower right atrium , unchanged since prior examination .