RELIAS Dysrhythmia Basic B Exam | 2025/2026 Edition,
focused on:Sinus & Atrial Rhythms (10 Verified Questions,
Answers & Rationales)
Aligned with AHA 2025 Guidelines and NCLEX-RN cardiac interpretation standards.
Each question includes:
RELIAS DYSRHYTHMIA BASIC B EXAM (2025/2026)
Section 1: Sinus & Atrial Rhythms (10 Questions)
1. What is the rate range for a normal sinus rhythm (NSR)?
A. 50–80 bpm
B. 60–100 bpm
C. 100–120 bpm
D. 40–60 bpm
✅ Answer: B. 60–100 bpm
Rationale: NSR originates from the SA node with normal rate, regular rhythm, and upright P waves in
lead II.
2. Which rhythm is defined by a sinus rate <60 bpm but otherwise normal morphology?
A. Sinus tachycardia
B. Sinus bradycardia
C. Junctional rhythm
D. Atrial fibrillation
✅ Answer: B. Sinus bradycardia
Rationale: Sinus bradycardia has a normal P-QRS-T sequence with slower rate; may occur in athletes or
with vagal stimulation.
3. Which medication could contribute to sinus bradycardia?
A. Albuterol
B. Atropine
C. Metoprolol
D. Epinephrine
, ✅ Answer: C. Metoprolol
Rationale: Beta-blockers and digoxin slow SA node firing and AV conduction, decreasing heart rate.
4. What defines sinus tachycardia on an ECG?
A. Rate above 100 bpm with upright P before each QRS
B. Irregular rhythm without P waves
C. Wide QRS and no P wave
D. Rate <60 bpm
✅ Answer: A. Rate above 100 bpm with upright P before each QRS
Rationale: The SA node fires faster; common in pain, anxiety, fever, or hypovolemia.
5. Which of the following best describes sinus arrhythmia?
A. Irregular rhythm associated with respiration
B. Fixed PR intervals with dropped QRS
C. Irregular ventricular rhythm without P waves
D. Chaotic atrial activity
✅ Answer: A. Irregular rhythm associated with respiration
Rationale: Heart rate increases with inspiration and decreases with expiration; common in young,
healthy individuals.
6. What is the initial nursing intervention for new-onset sinus bradycardia with hypotension?
A. Start IV fluids and notify provider
B. Administer amiodarone
C. Defibrillate immediately
D. Apply nitroglycerin
✅ Answer: A. Start IV fluids and notify provider
Rationale: Symptomatic bradycardia requires assessment of perfusion; atropine or pacing may follow if
unstable.
7. Which ECG finding distinguishes atrial flutter from atrial fibrillation?
A. Regular sawtooth F waves
B. Irregularly irregular rhythm
C. No identifiable atrial activity
D. Presence of normal P waves
✅ Answer: A. Regular sawtooth F waves
Rationale: Atrial flutter shows uniform “sawtooth” waves; AFib shows chaotic baseline and irregular
ventricular response.
focused on:Sinus & Atrial Rhythms (10 Verified Questions,
Answers & Rationales)
Aligned with AHA 2025 Guidelines and NCLEX-RN cardiac interpretation standards.
Each question includes:
RELIAS DYSRHYTHMIA BASIC B EXAM (2025/2026)
Section 1: Sinus & Atrial Rhythms (10 Questions)
1. What is the rate range for a normal sinus rhythm (NSR)?
A. 50–80 bpm
B. 60–100 bpm
C. 100–120 bpm
D. 40–60 bpm
✅ Answer: B. 60–100 bpm
Rationale: NSR originates from the SA node with normal rate, regular rhythm, and upright P waves in
lead II.
2. Which rhythm is defined by a sinus rate <60 bpm but otherwise normal morphology?
A. Sinus tachycardia
B. Sinus bradycardia
C. Junctional rhythm
D. Atrial fibrillation
✅ Answer: B. Sinus bradycardia
Rationale: Sinus bradycardia has a normal P-QRS-T sequence with slower rate; may occur in athletes or
with vagal stimulation.
3. Which medication could contribute to sinus bradycardia?
A. Albuterol
B. Atropine
C. Metoprolol
D. Epinephrine
, ✅ Answer: C. Metoprolol
Rationale: Beta-blockers and digoxin slow SA node firing and AV conduction, decreasing heart rate.
4. What defines sinus tachycardia on an ECG?
A. Rate above 100 bpm with upright P before each QRS
B. Irregular rhythm without P waves
C. Wide QRS and no P wave
D. Rate <60 bpm
✅ Answer: A. Rate above 100 bpm with upright P before each QRS
Rationale: The SA node fires faster; common in pain, anxiety, fever, or hypovolemia.
5. Which of the following best describes sinus arrhythmia?
A. Irregular rhythm associated with respiration
B. Fixed PR intervals with dropped QRS
C. Irregular ventricular rhythm without P waves
D. Chaotic atrial activity
✅ Answer: A. Irregular rhythm associated with respiration
Rationale: Heart rate increases with inspiration and decreases with expiration; common in young,
healthy individuals.
6. What is the initial nursing intervention for new-onset sinus bradycardia with hypotension?
A. Start IV fluids and notify provider
B. Administer amiodarone
C. Defibrillate immediately
D. Apply nitroglycerin
✅ Answer: A. Start IV fluids and notify provider
Rationale: Symptomatic bradycardia requires assessment of perfusion; atropine or pacing may follow if
unstable.
7. Which ECG finding distinguishes atrial flutter from atrial fibrillation?
A. Regular sawtooth F waves
B. Irregularly irregular rhythm
C. No identifiable atrial activity
D. Presence of normal P waves
✅ Answer: A. Regular sawtooth F waves
Rationale: Atrial flutter shows uniform “sawtooth” waves; AFib shows chaotic baseline and irregular
ventricular response.
