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RELIAS DYSRHYTHMIA BASIC A EXAM 2026/2027
COMPLETE (140) CURRENT TESTING QUESTIONS AND
CORRECT ANSWERS WITH DETAILED RATIONALES.
DYSRHYTHMIA
Prepare effectively for the Relias Dysrhythmia Basic A Exam with this focused study
resource. It supports review of essential cardiac rhythm concepts, ECG interpretation,
dysrhythmia recognition, heart conduction, and appropriate clinical responses. Use
the material to reinforce your understanding, review key topics, and identify areas that
may require additional study. This resource is suited for nurses, nursing students,
healthcare professionals, and learners preparing for the Relias Dysrhythmia Basic A
examination.
MULTIPLE CHOICE.
DOMAIN 1 — Cardiac Anatomy, Physiology & ECG Fundamentals
(Questions 1–14)
1. The normal pacemaker of the heart is the:
• A. Atrioventricular (AV) node
• B. Bundle of His
• C. Sinoatrial (SA) node
• D. Purkinje fibers
• Answer: C. Sinoatrial (SA) node
• Rationale: The SA node is the primary pacemaker of the heart,
generating electrical impulses at a rate of 60–100 beats per minute. It is
located in the right atrium and sets the baseline heart rate.
2. What is the normal duration of a PR interval on an ECG?
• A. 0.04–0.10 seconds
• B. 0.12–0.20 seconds
• C. 0.20–0.30 seconds
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• D. 0.30–0.40 seconds
• Answer: B. 0.12–0.20 seconds
• Rationale: The PR interval represents the time from the onset of atrial
depolarization to the onset of ventricular depolarization. Normal PR
interval is 0.12–0.20 seconds (3–5 small boxes).
3. What is the normal duration of a QRS complex?
• A. Less than 0.04 seconds
• B. 0.06–0.10 seconds
• C. 0.12–0.20 seconds
• D. Greater than 0.20 seconds
• Answer: B. 0.06–0.10 seconds
• Rationale: The QRS complex represents ventricular depolarization.
Normal QRS duration is 0.06–0.10 seconds (1.5–2.5 small boxes). A
wide QRS (>0.12 seconds) indicates a ventricular conduction delay.
4. In a normal ECG, the P wave represents:
• A. Ventricular depolarization
• B. Atrial depolarization
• C. Ventricular repolarization
• D. Atrial repolarization
• Answer: B. Atrial depolarization
• Rationale: The P wave represents atrial depolarization (contraction).
The QRS complex represents ventricular depolarization, and the T wave
represents ventricular repolarization.
5. Which lead is most commonly used for continuous cardiac monitoring
in a telemetry unit?
• A. Lead I
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• B. Lead II
• C. Lead III
• D. Lead V1
• Answer: B. Lead II
• Rationale: Lead II provides a clear view of the P wave and is most
commonly used for rhythm monitoring. It shows the electrical activity
between the right arm and left leg.
6. The QT interval represents:
• A. Atrial depolarization and repolarization
• B. Ventricular depolarization and repolarization
• C. AV node conduction time
• D. SA node firing rate
• Answer: B. Ventricular depolarization and repolarization
• Rationale: The QT interval represents the total time for ventricular
depolarization and repolarization. It is measured from the beginning of
the QRS complex to the end of the T wave.
7. Which structure is responsible for the delay in electrical conduction
that allows the atria to fully contract before ventricular contraction?
• A. SA node
• B. AV node
• C. Bundle branches
• D. Purkinje fibers
• Answer: B. AV node
• Rationale: The AV node slows the electrical impulse, providing a delay
that allows the atria to contract and fill the ventricles before ventricular
contraction occurs.
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8. On an ECG, one small box represents how many seconds?
• A. 0.04 seconds
• B. 0.10 seconds
• C. 0.20 seconds
• D. 0.40 seconds
• Answer: A. 0.04 seconds
• Rationale: On standard ECG paper running at 25 mm/second, one
small box (1 mm) equals 0.04 seconds. One large box (5 mm) equals
0.20 seconds.
9. The intrinsic firing rate of the AV node is approximately:
• A. 20–40 beats per minute
• B. 40–60 beats per minute
• C. 60–100 beats per minute
• D. 100–150 beats per minute
• Answer: B. 40–60 beats per minute
• Rationale: The AV node has an intrinsic firing rate of 40–60 bpm. The SA
node fires at 60–100 bpm, and the Purkinje fibers fire at 20–40 bpm.
10. The T wave on an ECG represents:
• A. Atrial depolarization
• B. Ventricular depolarization
• C. Ventricular repolarization
• D. Atrial repolarization
• Answer: C. Ventricular repolarization
• Rationale: The T wave represents ventricular repolarization, the
recovery of the ventricles after contraction. It is normally upright in most
leads.
RELIAS DYSRHYTHMIA BASIC A EXAM 2026/2027
COMPLETE (140) CURRENT TESTING QUESTIONS AND
CORRECT ANSWERS WITH DETAILED RATIONALES.
DYSRHYTHMIA
Prepare effectively for the Relias Dysrhythmia Basic A Exam with this focused study
resource. It supports review of essential cardiac rhythm concepts, ECG interpretation,
dysrhythmia recognition, heart conduction, and appropriate clinical responses. Use
the material to reinforce your understanding, review key topics, and identify areas that
may require additional study. This resource is suited for nurses, nursing students,
healthcare professionals, and learners preparing for the Relias Dysrhythmia Basic A
examination.
MULTIPLE CHOICE.
DOMAIN 1 — Cardiac Anatomy, Physiology & ECG Fundamentals
(Questions 1–14)
1. The normal pacemaker of the heart is the:
• A. Atrioventricular (AV) node
• B. Bundle of His
• C. Sinoatrial (SA) node
• D. Purkinje fibers
• Answer: C. Sinoatrial (SA) node
• Rationale: The SA node is the primary pacemaker of the heart,
generating electrical impulses at a rate of 60–100 beats per minute. It is
located in the right atrium and sets the baseline heart rate.
2. What is the normal duration of a PR interval on an ECG?
• A. 0.04–0.10 seconds
• B. 0.12–0.20 seconds
• C. 0.20–0.30 seconds
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• D. 0.30–0.40 seconds
• Answer: B. 0.12–0.20 seconds
• Rationale: The PR interval represents the time from the onset of atrial
depolarization to the onset of ventricular depolarization. Normal PR
interval is 0.12–0.20 seconds (3–5 small boxes).
3. What is the normal duration of a QRS complex?
• A. Less than 0.04 seconds
• B. 0.06–0.10 seconds
• C. 0.12–0.20 seconds
• D. Greater than 0.20 seconds
• Answer: B. 0.06–0.10 seconds
• Rationale: The QRS complex represents ventricular depolarization.
Normal QRS duration is 0.06–0.10 seconds (1.5–2.5 small boxes). A
wide QRS (>0.12 seconds) indicates a ventricular conduction delay.
4. In a normal ECG, the P wave represents:
• A. Ventricular depolarization
• B. Atrial depolarization
• C. Ventricular repolarization
• D. Atrial repolarization
• Answer: B. Atrial depolarization
• Rationale: The P wave represents atrial depolarization (contraction).
The QRS complex represents ventricular depolarization, and the T wave
represents ventricular repolarization.
5. Which lead is most commonly used for continuous cardiac monitoring
in a telemetry unit?
• A. Lead I
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• B. Lead II
• C. Lead III
• D. Lead V1
• Answer: B. Lead II
• Rationale: Lead II provides a clear view of the P wave and is most
commonly used for rhythm monitoring. It shows the electrical activity
between the right arm and left leg.
6. The QT interval represents:
• A. Atrial depolarization and repolarization
• B. Ventricular depolarization and repolarization
• C. AV node conduction time
• D. SA node firing rate
• Answer: B. Ventricular depolarization and repolarization
• Rationale: The QT interval represents the total time for ventricular
depolarization and repolarization. It is measured from the beginning of
the QRS complex to the end of the T wave.
7. Which structure is responsible for the delay in electrical conduction
that allows the atria to fully contract before ventricular contraction?
• A. SA node
• B. AV node
• C. Bundle branches
• D. Purkinje fibers
• Answer: B. AV node
• Rationale: The AV node slows the electrical impulse, providing a delay
that allows the atria to contract and fill the ventricles before ventricular
contraction occurs.
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8. On an ECG, one small box represents how many seconds?
• A. 0.04 seconds
• B. 0.10 seconds
• C. 0.20 seconds
• D. 0.40 seconds
• Answer: A. 0.04 seconds
• Rationale: On standard ECG paper running at 25 mm/second, one
small box (1 mm) equals 0.04 seconds. One large box (5 mm) equals
0.20 seconds.
9. The intrinsic firing rate of the AV node is approximately:
• A. 20–40 beats per minute
• B. 40–60 beats per minute
• C. 60–100 beats per minute
• D. 100–150 beats per minute
• Answer: B. 40–60 beats per minute
• Rationale: The AV node has an intrinsic firing rate of 40–60 bpm. The SA
node fires at 60–100 bpm, and the Purkinje fibers fire at 20–40 bpm.
10. The T wave on an ECG represents:
• A. Atrial depolarization
• B. Ventricular depolarization
• C. Ventricular repolarization
• D. Atrial repolarization
• Answer: C. Ventricular repolarization
• Rationale: The T wave represents ventricular repolarization, the
recovery of the ventricles after contraction. It is normally upright in most
leads.
