Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is post median sternotomy , mitral replacement . Left - sided defibrillator , with leads in the right atrium and right ventricle , is unchanged . Previously seen ill - defined nodular and hazy opacities in the right lung have greatly improved since the radiograph from 2 days prior , suggesting these were due to pulmonary edema . However , persistent opacities in the right could be due to residual asymmetric edema or infection .
    OUTPUT:
    
1 . Significant improvement in asymmetric right lung opacities , suggesting they were due to pulmonary edema . 2 . Persistent opacities in the right lung may be due to residual asymmetric edema or infection .