Electrocardiography (ECG) Quiz

What is the primary function of an electrocardiogram (ECG)?

• To perform heart surgery

• To assess cardiovascular health

• To analyze blood samples

• To measure blood pressure

Which node acts as the natural pacemaker of the heart?

• Atrioventricular Node

• Purkinje Fibers

• Bundle of His

• Sino-Atrial Node

What is the normal duration of the PR interval in an ECG?

• 0.20-0.25 s

• 0.25-0.30 s

• 0.10-0.15 s

• 0.12-0.20 s

How is the heart rate calculated using ECG paper?

• Count the number of small squares between R waves and divide by 1500

• Count the number of large squares between R waves and divide by 300

• Count the number of P waves

• Count the number of leads used

What does a downward deflection on an ECG indicate?

• Impulse traveling towards the electrode

• Impulse traveling away from the electrode

• Atrial contraction

• Normal heart rhythm

Which leads are considered bipolar limb leads?

• V5, V6, aVF

• I, II, III

• V1, V2, V3

• aVR, aVL, aVF

What does the T wave on an ECG represent?

• Atrial depolarization

• Atrial repolarization

• Ventricular depolarization

• Ventricular repolarization

What is the significance of the QT interval?

• It measures the time for atrial depolarization

• It indicates the heart rate

• It represents the total time for ventricular depolarization and repolarization

• It shows the amplitude of the QRS complex

Which lead is most commonly used to record a rhythm strip?

• Lead III

• Lead aVR

• Lead II

• Lead I

What is the effect of increased myocardial mass on ECG waveforms?

• Decreased amplitude

• Inverted waves

• Increased amplitude

• No effect