Twenty-five years of pacemaking.
D000368:Aged; D000818:Animals; D004285:Dogs; D004867:Equipment Design; D005260:Female; D049673:History, 20th Century; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial / Q000266:history*; D014481:United States