Contraction of the muscle fibers within the heart is controlled by electricity
Posted by admin on Nov 28, 2008
Contraction of the muscle fibers within the heart is controlled by electricity. This flows through the heart in a precise manner, along distinct pathways and at a controlled speed. The electrical current that begins each heartbeat, originates in the heart”s pacemaker, located in the top of the upper right heart chamber (right atrium). The rate at which the pacemaker discharges the electrical current determines the heart rate. This rate is influenced by nerve impulses and levels of certain hormones within the bloodstream.