EKG

1. P Wave

  • What it represents: Depolarization of the atria.

  • Heart action: Atria contract, pushing blood into the ventricles.

  • Time: Starts when the electrical impulse is generated by the SA node and spreads through the atria.

2. PR Interval

  • What it represents: The total time it takes for the electrical impulse to travel from the SA node, through the atria, the AV node, and to the Purkinje fibers.

  • Heart action: Atria finish contracting and ventricles begin filling with blood.

  • Time: From the start of the P wave to the start of the QRS complex.

3. PR Segment

  • What it represents: The period when the electrical impulse travels through the AV node.

  • Heart action: Electrical impulse slows in the AV node, allowing time for the ventricles to fill with blood.

  • Time: Flat line between the end of the P wave and the beginning of the QRS complex.

4. QRS Complex

  • What it represents: Depolarization of the ventricles.

  • Heart action: Ventricles contract, pumping blood to the lungs and the body.

  • Time: The duration from the start of the Q wave to the end of the S wave.

5. ST Segment

  • What it represents: The time during which the ventricular muscle cells remain depolarized.

  • Heart action: The ventricles are in a resting phase after contraction, before the next cycle begins.

  • Time: From the end of the S wave to the start of the T wave.

6. T Wave

  • What it represents: Repolarization of the ventricles.

  • Heart action: Ventricles relax and return to their resting state in preparation for the next contraction.

  • Time: The period from the peak of the T wave to the end.

7. QT Interval

  • What it represents: Total time it takes for the ventricles to depolarize and repolarize.

  • Heart action: Includes both ventricular contraction (depolarization) and relaxation (repolarization).

  • Time: From the start of the QRS complex to the end of the T wave.

8. TP Segment

  • What it represents: Electrical inactivity between the end of ventricular repolarization and the beginning of the next atrial depolarization.

  • Heart action: Both the atria and ventricles are relaxed and filling with blood.

  • Time: The flat line between the end of the T wave and the start of the next P wave.