Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Severely enlarged left main pulmonary artery is unchanged since ___ , documented by CTA of the chest on ___ . The cardiac silhouette is top normal size , but larger than in ___ . No pulmonary vascular congestion or pulmonary edema is detected . The inspiratory lung volumes are slightly lower . Within these limitations , there is no focal consolidation concerning for pneumonia , significant pleural effusion , or pneumothorax . The trachea is midline .
    OUTPUT:
    
1 . No acute cardiopulmonary process . 2 . Stable enlargement left main pulmonary artery since CT of ___ . Slight interval increase in heart size to top normal .