Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left chest tube is located at the left base . No pneumothorax is seen . ET tube is 4 .5 cm above the carinal . Median sternotomy wires are seen and are unremarkable . Right IJ introduced Swan - Ganz catheter terminates in the pulmonary outflow tract . A radio-opaque valve is seen , aortic valve replacement per___ medical records . There are no pleural effusions . Left lower lobe atelectasis is seen with air bronchograms . There is mild widening of the mediastinum especially right laterally which could be accounted for lower lung volumes , but is prudent to repeat and x-ray in the next ___hr .
    OUTPUT:
    
Interval resolution of right mainstem intubation with improved aeration of left lung . Widening of the mediastinum which may be related to lower lung volumes but repeat x-ray in the next ___hr is recommended .