Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . Triple lead left - sided pacemaker is again seen with leads similar in position . There is elevation of the left hemidiaphragm and slight blunting of the left costophrenic angle which may be due to a small pleural effusion with overlying atelectasis . Calcifications project over the left mid lung . No right pleural effusion is seen . The right lung is clear .
    OUTPUT:
    
Left base opacity may be due to combination of pleural effusion and atelectasis .