Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since ___ , new mild asymmetric pulmonary edema , right greater than left , is superimposed on the known chronic lung disease . Mild bibasilar atelectasis is noted . A small left pleural effusion is possible . The heart is mildly enlarged . Median sternotomy wires are intact and aligned . No pneumothorax . Partially imaged spinal fusion hardware is identified in the lumbar spine .
    OUTPUT:
    
New mild asymmetric pulmonary edema , right greater than left , is superimposed on known chronic lung disease .