Normal QRS duration is within which range?

Normal QRS duration is within which range?

• A. 0.04-0.12
• B. 0.04-0.08
• C. 0.06-0.14
• D. 0.08-0.16

Answer: (A)

QRS duration measures how long ventricular depolarization takes. In a normal heart, this happens quickly, so the QRS complex should last up to about 0.12 seconds. On standard ECG paper speed, 0.12 seconds spans three small boxes; together with the lower bound around 0.04 seconds, the normal range is roughly 0.04–0.12 seconds. This makes the range 0.04–0.12 seconds the best fit because it includes all normal durations, up to the upper limit. Durations longer than 0.12 seconds suggest some conduction delay, such as a bundle branch block or other ventricular conduction abnormality, while much shorter values are uncommon and not considered normal.

QRS duration measures how long ventricular depolarization takes. In a normal heart, this happens quickly, so the QRS complex should last up to about 0.12 seconds. On standard ECG paper speed, 0.12 seconds spans three small boxes; together with the lower bound around 0.04 seconds, the normal range is roughly 0.04–0.12 seconds. This makes the range 0.04–0.12 seconds the best fit because it includes all normal durations, up to the upper limit. Durations longer than 0.12 seconds suggest some conduction delay, such as a bundle branch block or other ventricular conduction abnormality, while much shorter values are uncommon and not considered normal.