Cardiovascular Physiology
Cardiac
Electrical Conduction
The SA Node is the hearts natural pacemaker. The autorhythmical cells generate electrical impulses which depolarize the atria, initiating the contraction of the atrial myocardial and stimulating the AV Node. The AV Node is connected to the Atrioventricular bundle which delivers impulses to the left and right bundle branches and eventually the purkinje fibers. This results in the depolarization and contraction of the ventricals.
The Electrocardiogram (ECG/EKG)
An electrocardiogram is a record of the heart's electrical activity. 12 leads, external skin sensors, are placed on the body to record the electrical impulses of the heart that cause it to contract. The depolarization of the cells causes the cardiac muscle to contract.
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*University of Utah
**Eastern Kentucky University