Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest demonstrate a retrocardiac opacity in the left lower lobe , with obscuration of the left hemidiaphragm on the frontal view , raising concern for aspiration or infection in the given clinical context . Small left pleural effusion is present . There is no evidence of pneumothorax . The visualized portions of the right lung are relatively clear , although the right costophrenic sulcus is excluded on the frontal view . No right pleural effusion is noted . The moderate cardiomegaly is unchanged without pulmonary vascular congestion . There is no subdiaphragmatic free air .
    OUTPUT:
    
1 . Left lower lobe opacity may reflect pneumonia or aspiration in the current clinical context with a small left pleural effusion . 2 . Stable moderate cardiomegaly .