Term
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Definition
| the syncronization of the heart functioning as a single unit |
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Term
| intrinsic conduction system |
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Definition
| nodal system: control system on heart activity with the nervous system. Consists of sepicalized noncontractile myocardial tissue. It ensures that heart muscle depolarizes in an orderly and sequential manner and that the heart beats as a coordinated unit. |
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Term
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Definition
| sinoatrial: part of the nodal system, located in the right atrium just inferior to the entrance to the superior vena cava, has the highest rate of discahrge, provides the stimulus for contractionreferred to as the PACEMAKER. From the SA node, the impulse spreads throughout the atria and to the AV node, followed by atrial contraction. |
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Term
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Definition
| atrioventricular node: in the lower atrial septum at the junction of the atria and ventricles, where the impulse is momentarily delayed, allowing the atria to complete their contraction, then the impulse passes through the AV bundle and to the right and left bundle branches...etc. |
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Term
| AV bundle (bundle of His) |
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Definition
| leads to the purkinje fibers |
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Term
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Definition
| long strands of barrel-shaped cells which ramify within the muscle bundles of the ventricular walls. Its network of fibers is much denser and more elaborate in the left ventricle because of the larger size of this chamber. |
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Term
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Definition
| makes a graphic recording of the electrical changes occurring during the cardiac cycle. |
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Term
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Definition
| the first wave in an ECG, is a small wave that indicates depolarization of the atria immediately before atrial contraction |
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Term
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Definition
| a larg spike-wave, resulting from ventricular depolarization, has a complicated shape. Precedes ventricular contraction. |
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Term
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Definition
| results from currents propagated during ventricular repolarization |
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Term
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Definition
| a heart rate over 100 bpm |
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Term
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Definition
| a heart rate below 60 bpm |
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Term
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Definition
| a condition which prolonged tachycardia may develop into. Is a condition of rapid uncoordinated heart contractions which makes the heart useless as a pump. |
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