Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are bilateral diffuse interstitial thickening and upper vascular re-distribution compatible with interstitial edema . There are no focal opacities suggestive of pneumonia . Heart size is mildly enlarged , although assessment is limited in this AP projection . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Interstitial pulmonary edema .