Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lungs are low in volume with dense retrocardiac and patchy right basal opacities , which may reflect atelectasis ; however , particularly on the left , pneumonia would be difficult to exclude . Accompanying pleural effusions may also be present . No pneumothorax is seen . The heart is moderately to markedly enlarged .
    OUTPUT:
    
1 . Dense retrocardiac opacity and bibasal opacities could reflect atelectasis and pleural effusion ; however , infectious process would be difficult to exclude . Accompanying pleural effusion , particularly on the left , may also be present . Consider PA and lateral examination with full inspiration to better assess . 2 . Moderate to marked cardiomegaly .