Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is markedly enlarged with a globular water bottle - like appearance that may reflect either pericardial effusion , marked cardiomegaly , or both . The mediastinal and hilar contours appear within normal limits . There is a perhaps mild upper zone re-distribution of pulmonary vascularity but no clear edema . No focal opacification is identified . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Marked cardiomegaly . In addition to enlargement of the heart , the possibility of a pericardial effusion should be considered .