EKG Question #17


On the electrocardiogram, which complex indicates both ventricular depolarization and repolarization?


  1. QT interval
    • Rationale:
  2. PR interval
    • Rationale:
  3. QS interval
    • Rationale:
  4. R-R interval
    • Rationale:



The QT interval represents the time of ventricular activity including both depolarization and repolarization and is measured from the beginning of the QRS complex to the end of the T wave. The QT interval is between 0.36 – 0.44 or approximately 9-11 small boxes. The QT interval varies with gender, age, heart rate, medical condition, and may vary are a result of medication adverse side effects.

Learning Outcomes

Test Taking Tip

Video Rationale