Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Known right lower lobe pulmonary nodule is not clearly delineated on this study . The lungs are otherwise clear with no evidence of a consolidation , effusion , or pneumothorax . Prominence of the right hilum remains stable and consistent with pulmonary artery hypertension . Cardiac and mediastinal silhouettes are stable . No acute fractures are identified .
    OUTPUT:
    
1 . No acute cardiopulmonary process . 2 . Known right lung base nodule is not clearly delineated on this study . 3 . Prominence of the right pulmonary artery likely reflects underlying pulmonary arterial hypertension .