RELIAS LEARNING
Dysrhythmia Basic B Exam
Cardiac Rhythm Interpretation
Official Practice Exam · 2026/2027 Edition
Questions: 35 Time: 90 Minutes Passing Score: 80% Recertification: Annual
Table of Contents
Cardiac Anatomy & Electrophysiology (Questions 1-8)
Rhythm Identification & Interpretation (Questions 9-20)
Dysrhythmia Classification & Clinical Significance (Questions 21-29)
Nursing Interventions & Patient Management (Questions 30-35)
Instructions
This practice exam contains 35 multiple-choice questions divided into four sections. You have 90 minutes to
complete the exam. A score of 80% or higher (28 out of 35 correct) is required to pass. Each question has four
answer choices (A through D). Select the single best answer for each question. Read each scenario carefully
before selecting your response. Review the rationale provided after each answer to reinforce your understanding of
cardiac rhythm interpretation concepts.
Exam Content Areas:
Section 1: Cardiac Anatomy & Electrophysiology - 8 questions (23%)
Section 2: Rhythm Identification & Interpretation - 12 questions (34%)
Section 3: Dysrhythmia Classification & Clinical Significance - 9 questions (26%)
Section 4: Nursing Interventions & Patient Management - 6 questions (17%)
RELIAS Dysrhythmia Basic B -- 2026/2027 | Passing Score: 80% | Page 1
,Section 1: Cardiac Anatomy & Electrophysiology | 2026/2027
Q1. Question 1 of 35
Q1. A 54-year-old male patient is admitted to the telemetry unit for evaluation of recurrent palpitations. The nurse
reviews the cardiac conduction system and recalls that the sinoatrial (SA) node normally initiates each heartbeat at a
rate of 60-100 impulses per minute. What structural feature allows the SA node to serve as the heart's primary
pacemaker?
A. It has the fastest intrinsic firing rate of all cardiac pacemaker cells
B. It is the only cardiac structure capable of spontaneous depolarization
C. It receives direct parasympathetic innervation exclusively without sympathetic input
D. It is located in the interventricular septum near the bundle of His
Correct Answer: A
Rationale:
The SA node has the fastest intrinsic firing rate (60-100 bpm), which allows it to dominate slower pacemakers like the AV node (40-60
bpm) and Purkinje fibers (20-40 bpm). Option B is incorrect because other cardiac cells (AV node, Purkinje fibers) also possess
automaticity, just at slower rates.
Q2. Question 2 of 35
Q2. A 67-year-old female presents with dizziness and fatigue. An ECG reveals a prolonged PR interval greater than
0.20 seconds. The nurse understands this finding indicates a delay in conduction through the atrioventricular (AV)
node. Which phase of the cardiac action potential is most responsible for the slow conduction through the AV node?
A. Phase 0 rapid depolarization mediated by fast sodium channels
B. Phase 2 plateau mediated by calcium channel influx
C. Phase 0 depolarization mediated primarily by slow calcium channels
D. Phase 3 repolarization mediated by potassium efflux
Correct Answer: C
Rationale:
AV nodal cells rely on slow calcium channel-mediated depolarization (Phase 0) rather than fast sodium channels, which produces their
characteristically slow conduction velocity. Option A describes ventricular muscle and Purkinje fiber depolarization, not AV nodal
conduction.
RELIAS Dysrhythmia Basic B -- 2026/2027 | Passing Score: 80% | Page 2
, Q3. Question 3 of 35
Q3. A 45-year-old patient undergoing cardiac monitoring has a heart rate of 88 bpm with a normal P wave preceding
each QRS complex. The nurse explains to the student that the P wave on the ECG represents atrial depolarization.
Which event immediately follows the P wave on the cardiac conduction cycle?
A. Ventricular repolarization beginning at the base of the heart
B. Impulse transmission through the AV node and His-Purkinje system
C. Atrial repolarization which is typically hidden within the QRS complex
D. Rapid ventricular depolarization producing the QRS complex
Correct Answer: B
Rationale:
After atrial depolarization (P wave), the impulse travels through the AV node and the His-Purkinje system before ventricular
depolarization occurs. Option C is partially true (atrial repolarization is hidden in the QRS) but is not the immediate next event in the
conduction sequence.
Q4. Question 4 of 35
Q4. A 72-year-old male with a history of myocardial infarction is found to have an idioventricular rhythm at 35 bpm on
telemetry. The nurse recognizes that this escape rhythm originates from the Purkinje fibers in the ventricles. What is
the intrinsic firing rate of ventricular pacemaker cells?
A. 20-40 impulses per minute
B. 40-60 impulses per minute
C. 60-100 impulses per minute
D. 100-150 impulses per minute
Correct Answer: A
Rationale:
Ventricular pacemaker cells (Purkinje fibers) have the slowest intrinsic firing rate at 20-40 bpm, which is why they serve as the
last-resort escape rhythm. Option B describes the AV node firing rate, not the ventricular escape rate.
Q5. Question 5 of 35
Q5. A 58-year-old woman is being monitored post-cardiac surgery. The nurse observes a wide QRS complex (0.14
seconds) on the rhythm strip. The nurse understands that a widened QRS complex indicates prolonged ventricular
depolarization. What is the normal duration of the QRS complex?
A. 0.04 to 0.10 seconds
B. 0.12 to 0.20 seconds
C. 0.20 to 0.28 seconds
D. 0.01 to 0.04 seconds
Correct Answer: A
RELIAS Dysrhythmia Basic B -- 2026/2027 | Passing Score: 80% | Page 3
Dysrhythmia Basic B Exam
Cardiac Rhythm Interpretation
Official Practice Exam · 2026/2027 Edition
Questions: 35 Time: 90 Minutes Passing Score: 80% Recertification: Annual
Table of Contents
Cardiac Anatomy & Electrophysiology (Questions 1-8)
Rhythm Identification & Interpretation (Questions 9-20)
Dysrhythmia Classification & Clinical Significance (Questions 21-29)
Nursing Interventions & Patient Management (Questions 30-35)
Instructions
This practice exam contains 35 multiple-choice questions divided into four sections. You have 90 minutes to
complete the exam. A score of 80% or higher (28 out of 35 correct) is required to pass. Each question has four
answer choices (A through D). Select the single best answer for each question. Read each scenario carefully
before selecting your response. Review the rationale provided after each answer to reinforce your understanding of
cardiac rhythm interpretation concepts.
Exam Content Areas:
Section 1: Cardiac Anatomy & Electrophysiology - 8 questions (23%)
Section 2: Rhythm Identification & Interpretation - 12 questions (34%)
Section 3: Dysrhythmia Classification & Clinical Significance - 9 questions (26%)
Section 4: Nursing Interventions & Patient Management - 6 questions (17%)
RELIAS Dysrhythmia Basic B -- 2026/2027 | Passing Score: 80% | Page 1
,Section 1: Cardiac Anatomy & Electrophysiology | 2026/2027
Q1. Question 1 of 35
Q1. A 54-year-old male patient is admitted to the telemetry unit for evaluation of recurrent palpitations. The nurse
reviews the cardiac conduction system and recalls that the sinoatrial (SA) node normally initiates each heartbeat at a
rate of 60-100 impulses per minute. What structural feature allows the SA node to serve as the heart's primary
pacemaker?
A. It has the fastest intrinsic firing rate of all cardiac pacemaker cells
B. It is the only cardiac structure capable of spontaneous depolarization
C. It receives direct parasympathetic innervation exclusively without sympathetic input
D. It is located in the interventricular septum near the bundle of His
Correct Answer: A
Rationale:
The SA node has the fastest intrinsic firing rate (60-100 bpm), which allows it to dominate slower pacemakers like the AV node (40-60
bpm) and Purkinje fibers (20-40 bpm). Option B is incorrect because other cardiac cells (AV node, Purkinje fibers) also possess
automaticity, just at slower rates.
Q2. Question 2 of 35
Q2. A 67-year-old female presents with dizziness and fatigue. An ECG reveals a prolonged PR interval greater than
0.20 seconds. The nurse understands this finding indicates a delay in conduction through the atrioventricular (AV)
node. Which phase of the cardiac action potential is most responsible for the slow conduction through the AV node?
A. Phase 0 rapid depolarization mediated by fast sodium channels
B. Phase 2 plateau mediated by calcium channel influx
C. Phase 0 depolarization mediated primarily by slow calcium channels
D. Phase 3 repolarization mediated by potassium efflux
Correct Answer: C
Rationale:
AV nodal cells rely on slow calcium channel-mediated depolarization (Phase 0) rather than fast sodium channels, which produces their
characteristically slow conduction velocity. Option A describes ventricular muscle and Purkinje fiber depolarization, not AV nodal
conduction.
RELIAS Dysrhythmia Basic B -- 2026/2027 | Passing Score: 80% | Page 2
, Q3. Question 3 of 35
Q3. A 45-year-old patient undergoing cardiac monitoring has a heart rate of 88 bpm with a normal P wave preceding
each QRS complex. The nurse explains to the student that the P wave on the ECG represents atrial depolarization.
Which event immediately follows the P wave on the cardiac conduction cycle?
A. Ventricular repolarization beginning at the base of the heart
B. Impulse transmission through the AV node and His-Purkinje system
C. Atrial repolarization which is typically hidden within the QRS complex
D. Rapid ventricular depolarization producing the QRS complex
Correct Answer: B
Rationale:
After atrial depolarization (P wave), the impulse travels through the AV node and the His-Purkinje system before ventricular
depolarization occurs. Option C is partially true (atrial repolarization is hidden in the QRS) but is not the immediate next event in the
conduction sequence.
Q4. Question 4 of 35
Q4. A 72-year-old male with a history of myocardial infarction is found to have an idioventricular rhythm at 35 bpm on
telemetry. The nurse recognizes that this escape rhythm originates from the Purkinje fibers in the ventricles. What is
the intrinsic firing rate of ventricular pacemaker cells?
A. 20-40 impulses per minute
B. 40-60 impulses per minute
C. 60-100 impulses per minute
D. 100-150 impulses per minute
Correct Answer: A
Rationale:
Ventricular pacemaker cells (Purkinje fibers) have the slowest intrinsic firing rate at 20-40 bpm, which is why they serve as the
last-resort escape rhythm. Option B describes the AV node firing rate, not the ventricular escape rate.
Q5. Question 5 of 35
Q5. A 58-year-old woman is being monitored post-cardiac surgery. The nurse observes a wide QRS complex (0.14
seconds) on the rhythm strip. The nurse understands that a widened QRS complex indicates prolonged ventricular
depolarization. What is the normal duration of the QRS complex?
A. 0.04 to 0.10 seconds
B. 0.12 to 0.20 seconds
C. 0.20 to 0.28 seconds
D. 0.01 to 0.04 seconds
Correct Answer: A
RELIAS Dysrhythmia Basic B -- 2026/2027 | Passing Score: 80% | Page 3
