Basics: Difference between revisions

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==The electric discharge of the heart==
==The electric discharge of the heart==
'''The sinal node (SA node) contains pacemakercells which determine the heart frequency.'''
[[Image:conduction_system_en.png|thumb|300px|The conduction system of the heart]]
'''The sinal node (SA node) contains the fastest physiological pacemaker cells of the heart, therefore they determine the [[Rate|heart rate]].'''
'''First the [[heart|atria]] depolarise and contract, after that the [[heart|ventricles]]'''
'''First the [[heart|atria]] depolarise and contract, after that the [[heart|ventricles]]'''
The electrical signal between the atria and the ventricles goes from the sinus node, via the atria to the AV-node (atrioventricular transition) to the His bundle and subsequently to the right and left bundle branch, which end in a dense network of Purkinje fibers.
The electrical signal between the atria and the ventricles goes from the sinus node, via the atria to the AV-node (atrioventricular transition) to the His bundle and subsequently to the right and left bundle branch, which end in a dense network of Purkinje fibers.
The depolarization of the heart results in an electrical force which has a direction and magnitude: an electrical vector. This vector changes every millisecond of the depolarization. In the animation vectors for atrial depolarization, ventricular depolarization and ventricular repolarization are shown.
The depolarization of the heart results in an electrical force which has a direction and magnitude: an electrical vector. This vector changes every millisecond of the depolarization. In the animation vectors for atrial depolarization, ventricular depolarization and ventricular repolarization are shown.
[[Image:conduction_system_en.png|thumb|300px|The conduction system of the heart]]
<flashow>http://nl.ecgpedia.org/images/b/bc/Normal_SR_vector.swf|height=300px</flashow>
<flashow>http://nl.ecgpedia.org/images/b/bc/Normal_SR_vector.swf|height=300px</flashow>
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