Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . The heart size is mildly enlarged with probable left atrial enlargement . Small opacity at the left costophrenic angle is most consistent with atelectasis . No pleural effusion or pneumothorax .
    OUTPUT:
    
1 . Small left costophrenic angle opacity consistent with atelectasis . 2 . Probable left atrial enlargement .