Which ECG pattern shows resting of the heart; repolarization?

Which ECG pattern shows resting of the heart; repolarization?

• A. Tracing
• B. ST segment
• C. Standard limb lead
• D. T wave

Answer: (D)

The heart’s electrical recovery after contraction is shown by the T wave. On an ECG, the sequence is P wave for atrial depolarization, QRS complex for ventricular depolarization (contraction), and then the T wave for ventricular repolarization, when the heart muscle returns to its resting electrical state. The ST segment sits between depolarization and repolarization and represents a period when the ventricles are depolarized and not yet repolarizing, so it isn’t the repolarization itself. Therefore, the resting/recovery phase of the ventricles is depicted by the T wave.

The heart’s electrical recovery after contraction is shown by the T wave. On an ECG, the sequence is P wave for atrial depolarization, QRS complex for ventricular depolarization (contraction), and then the T wave for ventricular repolarization, when the heart muscle returns to its resting electrical state. The ST segment sits between depolarization and repolarization and represents a period when the ventricles are depolarized and not yet repolarizing, so it isn’t the repolarization itself. Therefore, the resting/recovery phase of the ventricles is depicted by the T wave.