Florida State Paramedic Practice Exam

What is the normal width of the QRS complex in an ECG?

1. 0.08 seconds

2. 0.10 seconds

3. 0.12 seconds

4. 0.14 seconds

The correct answer is: 0.12 seconds

The normal width of the QRS complex in an electrocardiogram (ECG) typically measures between 0.06 to 0.10 seconds. A QRS complex duration of 0.12 seconds or more generally indicates a delay in ventricular conduction, such as seen in conditions like bundle branch block or other intraventricular conduction delays. Selection of a QRS width of 0.12 seconds conveys the understanding that the QRS complex can be prolonged, which is significant in clinical assessment. In healthy individuals, a narrower complex reflects efficient and quick conduction through the ventricles. Recognizing a QRS duration of 0.12 seconds or longer is important in assessing patient heart health and identifying underlying cardiac abnormalities that may require further investigation or intervention. Therefore, understanding where the normal limits lie helps in recognizing deviations that may signal potential issues within the cardiac conduction system.