Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are relatively low . Mild increase in interstitial markings diffusely bilaterally suggests interstitial edema . No definite focal consolidation is seen . There is possible trace pleural effusion posteriorly . No large pleural effusion is seen . The cardiac silhouette remains mildly to moderately enlarged . The patient is status post median sternotomy and cardiac valve replacement .
    OUTPUT:
    
Mild interstitial edema . Possible trace pleural effusion . Mild to moderate cardiomegaly .