Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There has been interval placement of a dual lead pacemaker . The pacemaker leads appear to be in appropriate position . No pneumothorax seen . No pleural effusion seen . An apparent retrocardiac opacity likely reflects atelectasis as this was not present on the prior study . Probable small bone infarct in the proximal right humerus .
    OUTPUT:
    
Expected appearances following pacemaker placement .