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   Pacemaker, natural
   Pacemaker, natural: The natural pacemaker of the heart is the sinus node, one of the major elements in the cardiac conduction system, the system that controls the heart rate. This stunningly designed system generates electrical impulses and conducts them throughout the muscle of the heart, stimulati...
   Found op http://www.medterms.com/script/main/art.html?articlekey=8446
   
   

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