- AV node), a cluster of cells situated in the center of the heart between the atria and ventricles. The AV node serves as a gate that slows the electrical current before the signal is permitted to pass down through to the ventricles. This delay ensures that the atria have a chance to fully contract before the ventricles are stimulated. After passing the AV node, the electrical current travels to the ventricles along special fibers embedded in the walls of the lower part of the heart.
Medical dictionary. 2011.
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Pacemaker (disambiguation) — Pacemaker may refer to:In biology and medicine: * Cardiac pacemaker, a group of cells within the heart that together initiate contractions and set the pace of beating * Artificial pacemaker, a device implanted to provide proper heart rhythm when… … Wikipedia
Pacemaker — A system that sends electrical impulses to the heart in order to set the heart rhythm. The pacemaker can be the normal natural pacemaker of the heart or it can be an electronic device. The natural pacemaker of the heart is the sinus node, one of… … Medical dictionary
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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… … Medical dictionary
pacemaker — n. (Physiol. & Anat.) 1. a specialized bit of heart tissue that controls the heartbeat. Syn: cardiac pacemaker, sinoatrial node. [WordNet 1.5] 2. An implanted electronic device that takes over the function of the natural cardiac pacemaker;… … The Collaborative International Dictionary of English
pacemaker — n. 1) a device used to produce and maintain a normal heart rate in patients who have heart block. The unit consists of a battery that stimulates the heart through an insulated electrode wire (lead) attached to the surface of the ventricle… … The new mediacal dictionary
Natural scientific research in Canada — This article outlines the history of natural scientific research in Canada, including mathematics, physics, astronomy, space science, geology, oceanography, chemistry, biology, medical research and psychology. The social sciences are not treated… … Wikipedia
pacemaker — n. 1 a competitor who sets the pace in a race. 2 a natural or artificial device for stimulating the heart muscle and determining the rate of its contractions … Useful english dictionary
Artificial pacemaker — Cardiac resynchronization therapy and CRT (Cardiac Resynchronization Therapy) redirect here. For the device termed a CRT D, see Implanted cardiac resynchronization device. For other uses, see Pacemaker (disambiguation). A pacemaker, scale in… … Wikipedia
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