Which ECG component is associated with ventricular depolarization?

Which ECG component is associated with ventricular depolarization?

• A. P wave
• B. QRS complex
• C. T wave
• D. U wave

Answer: (B)

Ventricular depolarization is the electrical activation that triggers the ventricles to contract. On the ECG, this rapid, coordinated activation appears as the QRS complex, the tall, sharp deflection that follows the P wave. The P wave represents atrial depolarization, which happens earlier, while the T wave shows ventricular repolarization (the ventricles resetting for the next beat). The U wave, when it appears, is not the primary indicator of ventricular depolarization and is less consistently seen. So, the component associated with ventricular depolarization is the QRS complex.

Ventricular depolarization is the electrical activation that triggers the ventricles to contract. On the ECG, this rapid, coordinated activation appears as the QRS complex, the tall, sharp deflection that follows the P wave. The P wave represents atrial depolarization, which happens earlier, while the T wave shows ventricular repolarization (the ventricles resetting for the next beat). The U wave, when it appears, is not the primary indicator of ventricular depolarization and is less consistently seen. So, the component associated with ventricular depolarization is the QRS complex.