Basics: Difference between revisions
→The ECG is a sum of the action potentials from millions of cardiomyocytes
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[[Image:cells_in_rest.png|thumb|In rest the heart cells are negatively charged. Trough the depolarization by surrounding cells they become positively charged and they contract.]] | [[Image:cells_in_rest.png|thumb|In rest the heart cells are negatively charged. Trough the depolarization by surrounding cells they become positively charged and they contract.]] | ||
[[Image:Ion_currents.jpg|thumb|During the depolarization sodium-ions stream inwards the cell. Subsequently the calcium-ions stream inwards the cell. These calcium-ions give the actual muscular contraction. Finally the potassium-ions stream out of the cell. During the repolarisation the ion concentration is corrected. On the ECG an action potential wave coming towards is shown as a positive result. Here the ECG electrode is represented as an eye.]] | [[Image:Ion_currents.jpg|thumb|During the depolarization sodium-ions stream inwards the cell. Subsequently the calcium-ions stream inwards the cell. These calcium-ions give the actual muscular contraction. Finally the potassium-ions stream out of the cell. During the repolarisation the ion concentration is corrected. On the ECG an action potential wave coming towards is shown as a positive result. Here the ECG electrode is represented as an eye.]] | ||
The individual [[action potential|action potentials]] of the individual cardiomyocytes are | The individual [[action potential|action potentials]] of the individual cardiomyocytes are averaged. The final result which is shown on the ECG is actually the average of trillions of microscopic electronical signals. | ||
{{clr}} | {{clr}} | ||