title: The present status of cardiac pacing.
mesh_terms: D000368:Aged; D001674:Bioelectric Energy Sources; D002104:Cadmium; D004566:Electrodes; D004567:Electrodes, Implanted; D004574:Electromagnetic Fields; D005260:Female; D006327:Heart Block / Q000628:therapy; D006801:Humans; D008094:Lithium; D008297:Male; D008628:Mercury; D008875:Middle Aged; D009532:Nickel; D009678:Nuclear Energy; D010138:Pacemaker, Artificial / Q000009:adverse effects / Q000295:instrumentation; D011005:Plutonium; D011399:Promethium; D015032:Zinc
chemical_list: D002104:Cadmium; D011005:Plutonium; D009532:Nickel; D008094:Lithium; D008628:Mercury; D015032:Zinc; D011399:Promethium