Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Post CABG changes are stable . Left prepectoral biventricular pacemaker in situ with the lead tips seen in the right atrium , right ventricle and coronary sinus / left ventricle . No left - sided pneumothorax . No airspace consolidation . Accessory azygos fissure . No pleural effusions . Degenerative changes of the bony elements .
    OUTPUT:
    
Biventricular lead tips in the appropriate positions . No left - sided pneumothorax .