Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . Relatively narrow mediastinal contour may be related to to known congenital heart disease . The lungs are clear without pleural effusion , focal consolidation , or pneumothorax . Mild rightward curvature of the upper thoracic spine noted .
    OUTPUT:
    
No acute intrathoracic process . Narrowed upper mediastinal contour is likely due to known congenital heart disease .