[HAADECGTechnologist] HAAD
ECGTechnologist DOH Licensureination for
ECG Technologist Certification Exam
Preparation
**Question 1.** Which structure initiates the electrical impulse in a normal heart?
A) Atrioventricular (AV) node
B) Purkinje fibers
C) Sinoatrial (SA) node
D) Bundle of His
Answer: C
Explanation: The SA node, located in the right atrium, is the primary pacemaker that generates
the impulse initiating each cardiac cycle.
**Question 2.** The normal duration of the PR interval on a standard ECG is:
A) 0.04–0.08 seconds
B) 0.12–0.20 seconds
C) 0.20–0.30 seconds
D) 0.30–0.40 seconds
Answer: B
Explanation: The PR interval reflects atrial depolarization and AV nodal conduction; normal
range is 120–200 ms (0.12–0.20 s).
**Question 3.** Which lead provides a view of the heart’s posterior wall when placed in the
seventh intercostal space at the midaxillary line?
A) V5
B) V6
C) V7
, [HAADECGTechnologist] HAAD
ECGTechnologist DOH Licensureination for
ECG Technologist Certification Exam
Preparation
D) aVL
Answer: C
Explanation: Posterior lead V7 is positioned at the posterior axillary line (5th intercostal space)
to assess the posterior left ventricle; V7–V9 extend this view.
**Question 4.** A patient’s ECG shows a QRS duration of 140 ms with a wide, bizarre
morphology. Which rhythm is most likely?
A) Supraventricular tachycardia (SVT)
B) Atrial flutter
C) Ventricular tachycardia (VT)
D) Sinus tachycardia
Answer: C
Explanation: Ventricular tachycardia typically presents with a wide QRS (>120 ms) and abnormal
morphology due to ventricular origin.
**Question 5.** Which electrolyte abnormality is most characteristically associated with tall,
peaked T‑waves?
A) Hypercalcemia
B) Hyperkalemia
C) Hypokalemia
D) Hypocalcemia
Answer: B
Explanation: Elevated serum potassium (hyperkalemia) leads to tall, narrow, peaked T‑waves on
the ECG.
, [HAADECGTechnologist] HAAD
ECGTechnologist DOH Licensureination for
ECG Technologist Certification Exam
Preparation
**Question 6.** During a 12‑lead ECG, which limb lead is recorded by placing the positive
electrode on the left arm?
A) Lead I
B) Lead II
C) Lead III
D) aVR
Answer: A
Explanation: Lead I measures the potential difference between the right arm (negative) and left
arm (positive) electrodes.
**Question 7.** Which of the following is the correct order of activation for the normal cardiac
conduction system?
A) AV node → SA node → Bundle of His → Purkinje fibers
B) SA node → AV node → Bundle of His → Purkinje fibers
C) Purkinje fibers → Bundle of His → AV node → SA node
D) Bundle of His → SA node → AV node → Purkinje fibers
Answer: B
Explanation: The impulse originates at the SA node, travels to the AV node, then through the
Bundle of His and Purkinje network to depolarize ventricles.
**Question 8.** Which artifact is most likely caused by a patient’s tremor during ECG
acquisition?
A) Baseline wander
, [HAADECGTechnologist] HAAD
ECGTechnologist DOH Licensureination for
ECG Technologist Certification Exam
Preparation
B) Muscle (EMG) artifact
C) Power‑line interference
D) Electrode motion artifact
Answer: B
Explanation: Muscle tremor generates high‑frequency EMG noise, appearing as a “shaky”
baseline.
**Question 9.** In a Holter monitor report, a “pause” of 3.2 seconds is noted. This finding is
most suggestive of:
A) Sinus tachycardia
B) Second‑degree AV block, type I
C) Sinus arrest or severe sinus bradycardia
D) Ventricular premature beats
Answer: C
Explanation: A pause >2.5 seconds often indicates sinus node dysfunction (arrest or marked
bradycardia).
**Question 10.** Which of the following is a contraindication to performing a treadmill stress
test?
A) Controlled hypertension
B) Recent myocardial infarction (within 48 h)
C) Stable angina
D) Beta‑blocker therapy
Answer: B
ECGTechnologist DOH Licensureination for
ECG Technologist Certification Exam
Preparation
**Question 1.** Which structure initiates the electrical impulse in a normal heart?
A) Atrioventricular (AV) node
B) Purkinje fibers
C) Sinoatrial (SA) node
D) Bundle of His
Answer: C
Explanation: The SA node, located in the right atrium, is the primary pacemaker that generates
the impulse initiating each cardiac cycle.
**Question 2.** The normal duration of the PR interval on a standard ECG is:
A) 0.04–0.08 seconds
B) 0.12–0.20 seconds
C) 0.20–0.30 seconds
D) 0.30–0.40 seconds
Answer: B
Explanation: The PR interval reflects atrial depolarization and AV nodal conduction; normal
range is 120–200 ms (0.12–0.20 s).
**Question 3.** Which lead provides a view of the heart’s posterior wall when placed in the
seventh intercostal space at the midaxillary line?
A) V5
B) V6
C) V7
, [HAADECGTechnologist] HAAD
ECGTechnologist DOH Licensureination for
ECG Technologist Certification Exam
Preparation
D) aVL
Answer: C
Explanation: Posterior lead V7 is positioned at the posterior axillary line (5th intercostal space)
to assess the posterior left ventricle; V7–V9 extend this view.
**Question 4.** A patient’s ECG shows a QRS duration of 140 ms with a wide, bizarre
morphology. Which rhythm is most likely?
A) Supraventricular tachycardia (SVT)
B) Atrial flutter
C) Ventricular tachycardia (VT)
D) Sinus tachycardia
Answer: C
Explanation: Ventricular tachycardia typically presents with a wide QRS (>120 ms) and abnormal
morphology due to ventricular origin.
**Question 5.** Which electrolyte abnormality is most characteristically associated with tall,
peaked T‑waves?
A) Hypercalcemia
B) Hyperkalemia
C) Hypokalemia
D) Hypocalcemia
Answer: B
Explanation: Elevated serum potassium (hyperkalemia) leads to tall, narrow, peaked T‑waves on
the ECG.
, [HAADECGTechnologist] HAAD
ECGTechnologist DOH Licensureination for
ECG Technologist Certification Exam
Preparation
**Question 6.** During a 12‑lead ECG, which limb lead is recorded by placing the positive
electrode on the left arm?
A) Lead I
B) Lead II
C) Lead III
D) aVR
Answer: A
Explanation: Lead I measures the potential difference between the right arm (negative) and left
arm (positive) electrodes.
**Question 7.** Which of the following is the correct order of activation for the normal cardiac
conduction system?
A) AV node → SA node → Bundle of His → Purkinje fibers
B) SA node → AV node → Bundle of His → Purkinje fibers
C) Purkinje fibers → Bundle of His → AV node → SA node
D) Bundle of His → SA node → AV node → Purkinje fibers
Answer: B
Explanation: The impulse originates at the SA node, travels to the AV node, then through the
Bundle of His and Purkinje network to depolarize ventricles.
**Question 8.** Which artifact is most likely caused by a patient’s tremor during ECG
acquisition?
A) Baseline wander
, [HAADECGTechnologist] HAAD
ECGTechnologist DOH Licensureination for
ECG Technologist Certification Exam
Preparation
B) Muscle (EMG) artifact
C) Power‑line interference
D) Electrode motion artifact
Answer: B
Explanation: Muscle tremor generates high‑frequency EMG noise, appearing as a “shaky”
baseline.
**Question 9.** In a Holter monitor report, a “pause” of 3.2 seconds is noted. This finding is
most suggestive of:
A) Sinus tachycardia
B) Second‑degree AV block, type I
C) Sinus arrest or severe sinus bradycardia
D) Ventricular premature beats
Answer: C
Explanation: A pause >2.5 seconds often indicates sinus node dysfunction (arrest or marked
bradycardia).
**Question 10.** Which of the following is a contraindication to performing a treadmill stress
test?
A) Controlled hypertension
B) Recent myocardial infarction (within 48 h)
C) Stable angina
D) Beta‑blocker therapy
Answer: B
