Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable semi-upright AP radiograph of the chest . The lung volumes are low . There is some blunting of the left costophrenic sulcus likely in the setting of atelectasis and small pleural effusion . The heart size is exaggerated by AP technique and is most likely top normal , stable . There is no pneumothorax . No new airspace opacity is seen to suggest pneumonia . There is crowding of central pulmonary vasculature , but no frank pulmonary edema .
    OUTPUT:
    
Low lung volumes with atelectasis and small pleural effusion at the left base but no convincing evidence of pneumonia .