CRAT ECG Waveform Measurements and Intervals 2

Question 1

The ST segment on the ECG represents:

Accepted Answer

The period between ventricular depolarization and repolarization

Answer

Atrial depolarization

Answer

AV node conduction delay

Answer

Ventricular filling time

Question 2

Which calculation method uses the number of large squares between two R waves to estimate heart rate?

Accepted Answer

300 divided by number of large squares

Answer

1500 divided by number of small squares

Answer

600 divided by number of large squares

Answer

60 divided by R-R interval in seconds

Question 3

What does a delta wave at the onset of the QRS complex suggest?

Accepted Answer

Pre-excitation syndrome (e.g., WPW)

Answer

Right bundle branch block

Answer

Hyperkalemia

Answer

Left ventricular hypertrophy

Question 4

An isoelectric baseline on the ECG refers to:

Accepted Answer

The normal baseline between waveforms with no electrical activity

Answer

A flat line indicating cardiac arrest

Answer

Prolonged asystole

Answer

Pacemaker spike artifact

Question 5

The normal amplitude (height) of the R wave in lead II is typically:

Accepted Answer

5–25 mm

Answer

Less than 1 mm

Answer

Greater than 35 mm

Answer

Equal in all leads

Question 6

Which interval is most commonly used to assess AV conduction time?

Accepted Answer

PR interval

Answer

QT interval

Answer

RR interval

Answer

ST segment duration