Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral chest radiographs demonstrate mild cardiomegaly and increased interstitial markings , including thickening of the interlobular septa . There may be a small pleural effusion on the left . There is no pneumothorax . The heart is mildly enlarged .
    OUTPUT:
    
Mild interstitial pulmonary edema .