Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is a pacemaker overlying the left chest , with leads that appear intact in the right atrium , right ventricle , and coronary sinus . There is no evidence of pneumothorax . There is atelectasis the left base , with a small pleural effusion . The right lung is clear . Heart size is stable . The mediastinal and hilar contours are stable . The pulmonary vasculature is normal . There are no acute osseous abnormalities .
    OUTPUT:
    
1 . Pacemaker in appropriate positioning without evidence of pneumothorax . 2 . Atelectasis at left base with a small pleural effusion .