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Relias Dysrhythmia Basic A Test (2025–2026)
| NGN-Style ECG Question Bank
Question 1: Recognizing Sinus Bradycardia
Clinical Scenario:
A 67-year-old male with a history of coronary artery disease presents for a routine physical. He
reports feeling "a bit tired lately" but denies dizziness, chest pain, or syncope. Vitals: HR 48
bpm, BP 128/76 mmHg, RR 16, Temp 36.8°C. A 12-lead ECG is ordered.
ECG Findings:
Regular rhythm
P wave before each QRS
PR interval: 0.18 seconds
QRS: 0.08 seconds
Rate: 48 bpm
Question:
Which rhythm is most consistent with this patient’s ECG?
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A. First-degree AV block
B. Sinus bradycardia
C. Junctional rhythm
D. Second-degree AV block, Type I
Correct Answer:
B. Sinus bradycardia
Rationale:
This ECG shows a regular sinus rhythm with a slow rate (<60 bpm). All P waves are upright
and followed by QRS complexes. The PR interval is within normal limits (0.12–0.20 seconds),
and QRS is narrow (<0.12 seconds), indicating that the rhythm originates in the SA node. This is
classic sinus bradycardia. In asymptomatic patients like this one, it may not require treatment.
First-degree AV block would show prolonged PR intervals, while junctional rhythms often have
absent or inverted P waves. Second-degree AV blocks would have irregular dropped beats.
Question 2: Identifying Atrial Fibrillation
Clinical Scenario:
An 81-year-old woman is admitted for fatigue and shortness of breath. She denies chest pain.
Vitals: HR 112 bpm (irregular), BP 134/80 mmHg, RR 18. ECG is ordered to evaluate her
rhythm.
ECG Findings:
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Irregularly irregular rhythm
No identifiable P waves
Variable R-R intervals
Narrow QRS complexes
Question:
What is the most likely rhythm?
A. Atrial flutter with variable block
B. Sinus tachycardia
C. Atrial fibrillation
D. Supraventricular tachycardia (SVT)
Correct Answer:
C. Atrial fibrillation
Rationale:
This ECG demonstrates atrial fibrillation (AFib), characterized by no visible P waves,
irregularly irregular rhythm, and narrow QRS complexes. The atria are fibrillating
chaotically, producing no effective contraction. AFib is common in older adults and can cause
fatigue and dyspnea due to decreased cardiac output. Atrial flutter usually has a sawtooth pattern
with regular atrial activity. Sinus tachycardia would have P waves, and SVT is typically very fast
and regular. The absence of P waves and an irregular rhythm confirms AFib.
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Question 3: Differentiating Ventricular Tachycardia
Clinical Scenario:
A 59-year-old man collapses while mowing the lawn. EMS arrives to find him unresponsive with
no palpable pulse. The cardiac monitor shows a wide-complex tachycardia.
ECG Findings:
Rate: ~160 bpm
Wide QRS complexes
No visible P waves
Regular rhythm
Question:
Which rhythm best describes this ECG?
A. Ventricular tachycardia
B. Supraventricular tachycardia with aberrancy
C. Ventricular fibrillation
D. Atrial flutter with 1:1 conduction
Correct Answer:
A. Ventricular tachycardia
Rationale:
This is a classic presentation of pulseless ventricular tachycardia (VT) — a life-threatening
rhythm requiring immediate defibrillation. Wide QRS complexes (>0.12 seconds), a regular
Relias Dysrhythmia Basic A Test (2025–2026)
| NGN-Style ECG Question Bank
Question 1: Recognizing Sinus Bradycardia
Clinical Scenario:
A 67-year-old male with a history of coronary artery disease presents for a routine physical. He
reports feeling "a bit tired lately" but denies dizziness, chest pain, or syncope. Vitals: HR 48
bpm, BP 128/76 mmHg, RR 16, Temp 36.8°C. A 12-lead ECG is ordered.
ECG Findings:
Regular rhythm
P wave before each QRS
PR interval: 0.18 seconds
QRS: 0.08 seconds
Rate: 48 bpm
Question:
Which rhythm is most consistent with this patient’s ECG?
, 2
A. First-degree AV block
B. Sinus bradycardia
C. Junctional rhythm
D. Second-degree AV block, Type I
Correct Answer:
B. Sinus bradycardia
Rationale:
This ECG shows a regular sinus rhythm with a slow rate (<60 bpm). All P waves are upright
and followed by QRS complexes. The PR interval is within normal limits (0.12–0.20 seconds),
and QRS is narrow (<0.12 seconds), indicating that the rhythm originates in the SA node. This is
classic sinus bradycardia. In asymptomatic patients like this one, it may not require treatment.
First-degree AV block would show prolonged PR intervals, while junctional rhythms often have
absent or inverted P waves. Second-degree AV blocks would have irregular dropped beats.
Question 2: Identifying Atrial Fibrillation
Clinical Scenario:
An 81-year-old woman is admitted for fatigue and shortness of breath. She denies chest pain.
Vitals: HR 112 bpm (irregular), BP 134/80 mmHg, RR 18. ECG is ordered to evaluate her
rhythm.
ECG Findings:
, 3
Irregularly irregular rhythm
No identifiable P waves
Variable R-R intervals
Narrow QRS complexes
Question:
What is the most likely rhythm?
A. Atrial flutter with variable block
B. Sinus tachycardia
C. Atrial fibrillation
D. Supraventricular tachycardia (SVT)
Correct Answer:
C. Atrial fibrillation
Rationale:
This ECG demonstrates atrial fibrillation (AFib), characterized by no visible P waves,
irregularly irregular rhythm, and narrow QRS complexes. The atria are fibrillating
chaotically, producing no effective contraction. AFib is common in older adults and can cause
fatigue and dyspnea due to decreased cardiac output. Atrial flutter usually has a sawtooth pattern
with regular atrial activity. Sinus tachycardia would have P waves, and SVT is typically very fast
and regular. The absence of P waves and an irregular rhythm confirms AFib.
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Question 3: Differentiating Ventricular Tachycardia
Clinical Scenario:
A 59-year-old man collapses while mowing the lawn. EMS arrives to find him unresponsive with
no palpable pulse. The cardiac monitor shows a wide-complex tachycardia.
ECG Findings:
Rate: ~160 bpm
Wide QRS complexes
No visible P waves
Regular rhythm
Question:
Which rhythm best describes this ECG?
A. Ventricular tachycardia
B. Supraventricular tachycardia with aberrancy
C. Ventricular fibrillation
D. Atrial flutter with 1:1 conduction
Correct Answer:
A. Ventricular tachycardia
Rationale:
This is a classic presentation of pulseless ventricular tachycardia (VT) — a life-threatening
rhythm requiring immediate defibrillation. Wide QRS complexes (>0.12 seconds), a regular
