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RELIAS DYSRHYTHMIA BASIC TEST ACTUAL 2026/2027 |
Verified Questions & Answers | Complete ECG Rhythm
Interpretation | Pass Guaranteed - A+ Graded
Section 1: Normal Sinus Rhythm & Sinus Dysrhythmias (Q1-12)
Q1. A patient on the telemetry unit has a rhythm strip showing a regular R-R interval,
rate of 72 bpm, upright P wave before each QRS complex, PR interval of 0.16
seconds, and narrow QRS duration. Which rhythm is present?
A. Sinus bradycardia
B. Normal sinus rhythm
C. Junctional rhythm
D. First-degree AV block
B. Normal sinus rhythm [CORRECT]
Rationale: The rhythm meets all criteria for normal sinus rhythm: rate 60-100 bpm,
regular rhythm, upright P wave preceding each QRS, PR interval 0.12-0.20 seconds,
and QRS <0.12 seconds. Sinus bradycardia would have a rate <60 bpm, junctional
rhythm would have absent or inverted P waves, and first-degree AV block would
have a PR interval >0.20 seconds.
Correct Answer: B
Q2. During morning vital signs, a 28-year-old marathon runner is found to have a
heart rate of 52 bpm. The telemetry strip shows a regular rhythm with normal P
waves, PR interval 0.14 seconds, and narrow QRS complexes. What is the most likely
rhythm?
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A. Normal sinus rhythm
B. Sinus bradycardia
C. Junctional escape rhythm
D. Third-degree AV block
B. Sinus bradycardia [CORRECT]
Rationale: A sinus rhythm with a rate <60 bpm is classified as sinus bradycardia. The
presence of normal upright P waves with a consistent PR interval confirms the
impulse originates from the SA node. Well-conditioned athletes commonly have
physiologic sinus bradycardia; junctional and third-degree AV block would show
abnormal or dissociated P wave activity.
Correct Answer: B
Q3. A post-operative patient receiving morphine via PCA pump develops a heart rate
of 58 bpm. The rhythm strip reveals upright P waves before each QRS, regular R-R
intervals, and a PR interval of 0.18 seconds. Which intervention is most appropriate?
A. Immediate transcutaneous pacing
B. Administration of atropine 0.5 mg IV
C. Continue monitoring; no immediate treatment required if asymptomatic
D. Prepare for emergent cardioversion
C. Continue monitoring; no immediate treatment required if asymptomatic
[CORRECT]
Rationale: Sinus bradycardia in an asymptomatic patient does not require immediate
pharmacologic intervention. Atropine is indicated for symptomatic bradycardia
(hypotension, altered mental status, chest pain), and transcutaneous pacing is
reserved for unstable or unresponsive patients. Morphine can cause vagal-mediated
bradycardia that resolves with monitoring.
Correct Answer: C
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Q4. A telemetry strip shows a rhythm with a rate of 118 bpm, regular R-R intervals,
upright P waves preceding each QRS complex, PR interval 0.15 seconds, and narrow
QRS complexes. The patient has a temperature of 38.9°C (102°F). What rhythm is
present?
A. Atrial tachycardia
B. Sinus tachycardia
C. Supraventricular tachycardia (SVT)
D. Junctional tachycardia
B. Sinus tachycardia [CORRECT]
Rationale: Sinus tachycardia is defined as a sinus rhythm with a rate >100 bpm,
characterized by upright P waves and a normal PR interval. Fever is a common
physiologic cause of sinus tachycardia. Atrial tachycardia and SVT typically have
abnormal or buried P waves, while junctional tachycardia would demonstrate
inverted or retrograde P waves.
Correct Answer: B
Q5. A rhythm strip shows a gradually increasing R-R interval during inspiration and a
gradually decreasing R-R interval during expiration. The rate varies between 62 and
88 bpm. P waves are upright and normal, with a constant PR interval of 0.16 seconds.
What is this rhythm?
A. Sinus arrhythmia
B. Sinus tachycardia with PACs
C. Atrial fibrillation
D. Second-degree AV block Type I
A. Sinus arrhythmia [CORRECT]
Rationale: Sinus arrhythmia is characterized by a phasic variation in heart rate
corresponding with respiration (rate increases with inspiration, decreases with
expiration), with normal P wave morphology and a constant PR interval. This is a
normal finding, particularly in young healthy individuals, and must be distinguished
from PACs, which would show premature P waves with different morphology.
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Correct Answer: A
Q6. A patient is found to have a sinus rhythm at 48 bpm after receiving atenolol for
hypertension. The strip shows upright P waves, regular rhythm, PR 0.20 seconds, and
narrow QRS. Which factor is the most likely cause?
A. Hypovolemia
B. Beta-blocker medication effect
C. Acute myocardial infarction
D. Hyperthyroidism
B. Beta-blocker medication effect [CORRECT]
Rationale: Beta-blockers such as atenolol block beta-1 adrenergic receptors, reducing
SA node automaticity and causing sinus bradycardia. Hypovolemia and
hyperthyroidism typically cause tachycardia, and while acute MI can cause
bradycardia (especially inferior wall), the recent administration of a beta-blocker is
the most direct and likely cause in this scenario.
Correct Answer: B
Q7. A telemetry strip shows a sinus rhythm at 52 bpm. The P waves are upright and
normal, but there is a sudden pause with no P wave, QRS complex, or T wave. After
the pause, the normal sinus rhythm resumes. The pause duration is not a multiple of
the underlying R-R interval. What is this rhythm?
A. Sinus arrhythmia
B. Sinus pause/arrest
C. Second-degree AV block Type I
D. Sinus exit block
B. Sinus pause/arrest [CORRECT]
Rationale: Sinus pause (or sinus arrest) is identified by a sudden absence of P waves,
QRS complexes, and T waves due to failure of the SA node to depolarize. The pause
RELIAS DYSRHYTHMIA BASIC TEST ACTUAL 2026/2027 |
Verified Questions & Answers | Complete ECG Rhythm
Interpretation | Pass Guaranteed - A+ Graded
Section 1: Normal Sinus Rhythm & Sinus Dysrhythmias (Q1-12)
Q1. A patient on the telemetry unit has a rhythm strip showing a regular R-R interval,
rate of 72 bpm, upright P wave before each QRS complex, PR interval of 0.16
seconds, and narrow QRS duration. Which rhythm is present?
A. Sinus bradycardia
B. Normal sinus rhythm
C. Junctional rhythm
D. First-degree AV block
B. Normal sinus rhythm [CORRECT]
Rationale: The rhythm meets all criteria for normal sinus rhythm: rate 60-100 bpm,
regular rhythm, upright P wave preceding each QRS, PR interval 0.12-0.20 seconds,
and QRS <0.12 seconds. Sinus bradycardia would have a rate <60 bpm, junctional
rhythm would have absent or inverted P waves, and first-degree AV block would
have a PR interval >0.20 seconds.
Correct Answer: B
Q2. During morning vital signs, a 28-year-old marathon runner is found to have a
heart rate of 52 bpm. The telemetry strip shows a regular rhythm with normal P
waves, PR interval 0.14 seconds, and narrow QRS complexes. What is the most likely
rhythm?
,2
A. Normal sinus rhythm
B. Sinus bradycardia
C. Junctional escape rhythm
D. Third-degree AV block
B. Sinus bradycardia [CORRECT]
Rationale: A sinus rhythm with a rate <60 bpm is classified as sinus bradycardia. The
presence of normal upright P waves with a consistent PR interval confirms the
impulse originates from the SA node. Well-conditioned athletes commonly have
physiologic sinus bradycardia; junctional and third-degree AV block would show
abnormal or dissociated P wave activity.
Correct Answer: B
Q3. A post-operative patient receiving morphine via PCA pump develops a heart rate
of 58 bpm. The rhythm strip reveals upright P waves before each QRS, regular R-R
intervals, and a PR interval of 0.18 seconds. Which intervention is most appropriate?
A. Immediate transcutaneous pacing
B. Administration of atropine 0.5 mg IV
C. Continue monitoring; no immediate treatment required if asymptomatic
D. Prepare for emergent cardioversion
C. Continue monitoring; no immediate treatment required if asymptomatic
[CORRECT]
Rationale: Sinus bradycardia in an asymptomatic patient does not require immediate
pharmacologic intervention. Atropine is indicated for symptomatic bradycardia
(hypotension, altered mental status, chest pain), and transcutaneous pacing is
reserved for unstable or unresponsive patients. Morphine can cause vagal-mediated
bradycardia that resolves with monitoring.
Correct Answer: C
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Q4. A telemetry strip shows a rhythm with a rate of 118 bpm, regular R-R intervals,
upright P waves preceding each QRS complex, PR interval 0.15 seconds, and narrow
QRS complexes. The patient has a temperature of 38.9°C (102°F). What rhythm is
present?
A. Atrial tachycardia
B. Sinus tachycardia
C. Supraventricular tachycardia (SVT)
D. Junctional tachycardia
B. Sinus tachycardia [CORRECT]
Rationale: Sinus tachycardia is defined as a sinus rhythm with a rate >100 bpm,
characterized by upright P waves and a normal PR interval. Fever is a common
physiologic cause of sinus tachycardia. Atrial tachycardia and SVT typically have
abnormal or buried P waves, while junctional tachycardia would demonstrate
inverted or retrograde P waves.
Correct Answer: B
Q5. A rhythm strip shows a gradually increasing R-R interval during inspiration and a
gradually decreasing R-R interval during expiration. The rate varies between 62 and
88 bpm. P waves are upright and normal, with a constant PR interval of 0.16 seconds.
What is this rhythm?
A. Sinus arrhythmia
B. Sinus tachycardia with PACs
C. Atrial fibrillation
D. Second-degree AV block Type I
A. Sinus arrhythmia [CORRECT]
Rationale: Sinus arrhythmia is characterized by a phasic variation in heart rate
corresponding with respiration (rate increases with inspiration, decreases with
expiration), with normal P wave morphology and a constant PR interval. This is a
normal finding, particularly in young healthy individuals, and must be distinguished
from PACs, which would show premature P waves with different morphology.
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Correct Answer: A
Q6. A patient is found to have a sinus rhythm at 48 bpm after receiving atenolol for
hypertension. The strip shows upright P waves, regular rhythm, PR 0.20 seconds, and
narrow QRS. Which factor is the most likely cause?
A. Hypovolemia
B. Beta-blocker medication effect
C. Acute myocardial infarction
D. Hyperthyroidism
B. Beta-blocker medication effect [CORRECT]
Rationale: Beta-blockers such as atenolol block beta-1 adrenergic receptors, reducing
SA node automaticity and causing sinus bradycardia. Hypovolemia and
hyperthyroidism typically cause tachycardia, and while acute MI can cause
bradycardia (especially inferior wall), the recent administration of a beta-blocker is
the most direct and likely cause in this scenario.
Correct Answer: B
Q7. A telemetry strip shows a sinus rhythm at 52 bpm. The P waves are upright and
normal, but there is a sudden pause with no P wave, QRS complex, or T wave. After
the pause, the normal sinus rhythm resumes. The pause duration is not a multiple of
the underlying R-R interval. What is this rhythm?
A. Sinus arrhythmia
B. Sinus pause/arrest
C. Second-degree AV block Type I
D. Sinus exit block
B. Sinus pause/arrest [CORRECT]
Rationale: Sinus pause (or sinus arrest) is identified by a sudden absence of P waves,
QRS complexes, and T waves due to failure of the SA node to depolarize. The pause
