Relias Dysrhythmia Basic Test 35 Questions and Answers
2026/2027 (Basic A Dysrhythmia)
200 Practice Questions with Detailed Answers & Explanations
for Exam Success
Section 1: Normal Sinus Rhythm & Sinus Rhythms (Qs 1-20)
1. A patient's telemetry strip shows a heart rhythm with a P wave before every QRS complex. The P
waves are upright and uniform. The heart rate is 72 beats/min. What is the rhythm?
- A) Sinus Bradycardia
- B) Normal Sinus Rhythm
- C) Sinus Tachycardia
- D) Junctional Rhythm
Answer: B
Normal Sinus Rhythm (NSR) is identified by a regular rhythm at rest (60–100 bpm), upright and
consistent P waves, a PR interval of 0.12–0.20 sec, and a QRS of <0.12 sec. This is the baseline rhythm
against which all other rhythms are compared. It indicates that the SA node is correctly pacing the heart
with normal conduction.
2. A patient's heart rate is 140 beats/min with regular rhythm. The P wave is upright, PR interval 0.16
sec, and QRS duration 0.08 sec. The patient is anxious after a minor medical procedure. What is the
rhythm?
- A) Normal Sinus Rhythm
- B) Sinus Tachycardia
- C) Supraventricular Tachycardia
- D) Atrial Flutter
Answer: B
,Sinus Tachycardia originates from the SA node and is characterized by a rate greater than 100 bpm
(usually 100–150 bpm) with a regular rhythm, normal P wave morphology, and normal PR and QRS
intervals. Anxiety, exercise, and fever are common causes. The key distinction from more serious SVT is
(a) the presence of normal, upright P waves before each QRS and (b) a gradual onset/offset.
3. A patient’s rhythm strip has a heart rate of 48 bpm. The P waves are upright and precede every QRS.
The PR interval is normal at 0.18 sec. The QRS is narrow (<0.12 sec). What is the most likely rhythm?
- A) Normal Sinus Rhythm
- B) Sinus Bradycardia
- C) Sinus Arrest
- D) Junctional Rhythm
Answer: B
Sinus Bradycardia is defined as a sinus rhythm (upright P wave, normal conduction) with a rate below 60
bpm. In this case, with a rate of 48 bpm and normal P waves, it is sinus bradycardia. This rhythm is often
well tolerated in healthy individuals (e.g., athletes) but can cause symptoms in others due to decreased
cardiac output.
4. Which of the following is a characteristic of Sinus Arrhythmia?
- A) The rhythm is irregular, with the rate increasing during inspiration and decreasing during expiration
- B) P waves are absent
- C) The rhythm is regularly irregular with dropped QRS complexes
- D) The PR interval is prolonged and variable
Answer: A
Sinus arrhythmia is a variant of normal sinus rhythm where the heart rate varies with the respiratory
cycle. The HR increases during inspiration (due to decreased vagal tone) and decreases during
expiration. The rhythm is irregular, but the EKG morphology remains normal. This is most common in
young, healthy people and is generally benign.
5. A patient has a regular rhythm at a rate of 40 bpm. The P wave is upright and normal in shape. The PR
interval is 0.16 sec and QRS width is 0.08 sec. The patient is asymptomatic and has been a long-distance
runner for 20 years. What is the most appropriate action?
,- A) Prepare for temporary pacing
- B) Administer atropine 0.5 mg IV push
- C) Recognize this as a normal finding in an athletic heart and document
- D) Notify the physician for a stat cardiology consult
Answer: C
A heart rate of 40 bpm with sinus bradycardia in a well-conditioned athlete is likely a normal physiologic
adaptation. The patient’s asymptomatic status is key; no intervention is required. Treatment for sinus
bradycardia is only indicated if the patient is symptomatic (hypotension, chest pain, syncope, altered
mental status).
6. A patient’s heart rate is in the range of 110–120 bpm. The rhythm is regular. P waves are upright and
each is followed by a QRS. The QRS duration is <0.12 sec. The patient complains of palpitations after
drinking a large caffeinated soda. What is the rhythm?
- A) Sinus Tachycardia
- B) Atrial Fibrillation
- C) Ventricular Tachycardia
- D) Atrial Flutter
Answer: A
This describes Sinus Tachycardia. The SA node fires faster than 100 bpm in response to a physiologic
stressor (in this case, caffeine). The rhythm remains regular, and the conduction sequence is normal.
The patient is aware of palpitations, but the rhythm itself is benign and typically resolves with removal
of the stimulus.
7. You are reviewing a rhythm strip. The rate is 62 bpm, but the P waves are obscured by large T waves.
What six-second strip technique should you use to double-check the rate?
- A) Count the number of R waves in a 6-second strip and multiply by 10
- B) Divide 300 by the number of large boxes between R waves
- C) Count the number of P waves in a 6-second strip and multiply by 10
- D) Look at the QRS duration only
, Answer: A
The most accurate method for an irregular rhythm or when P waves are hard to see is the 6-second strip
method. You count the number of R waves in a 6-second strip (there are 30 large boxes or 3 seconds per
1-inch mark in standard recording). Multiply that count by 10 to get the rate. The 300 method (divide by
the number of large boxes between R waves) is only accurate for regular rhythms.
8. In Normal Sinus Rhythm, what is the correct duration for the PR interval?
- A) 0.20–0.40 seconds
- B) 0.12–0.20 seconds
- C) >0.20 seconds
- D) <0.10 seconds
Answer: B
The PR interval, measured from the onset of the P wave to the onset of the QRS complex, represents the
time for the impulse to travel from the SA node through the atria and the AV node, where it is delayed.
In a healthy conducting system, this takes 0.12–0.20 seconds (3–5 small boxes). A PR interval >0.20
seconds indicates a first-degree AV block.
9. Which lead is considered the "rhythm strip" most commonly used for telemetry monitoring?
- A) Lead aVL
- B) Lead V3
- C) Lead II
- D) Lead aVF
Answer: C
Lead II is the most frequently used lead for continuous telemetry and rhythm strips because it provides a
clear view of the P wave and aligns with the heart’s electrical axis. Long strips from Lead II are standard
for analyzing rhythm regularity.
10. An elderly patient is found to have a heart rate of 52 bpm. The EKG shows a regular rhythm with
upright P waves before each QRS, PR interval 0.18 sec, QRS 0.08 sec. The patient reports feeling tired
and lightheaded. Which of the following is the most appropriate initial intervention?
2026/2027 (Basic A Dysrhythmia)
200 Practice Questions with Detailed Answers & Explanations
for Exam Success
Section 1: Normal Sinus Rhythm & Sinus Rhythms (Qs 1-20)
1. A patient's telemetry strip shows a heart rhythm with a P wave before every QRS complex. The P
waves are upright and uniform. The heart rate is 72 beats/min. What is the rhythm?
- A) Sinus Bradycardia
- B) Normal Sinus Rhythm
- C) Sinus Tachycardia
- D) Junctional Rhythm
Answer: B
Normal Sinus Rhythm (NSR) is identified by a regular rhythm at rest (60–100 bpm), upright and
consistent P waves, a PR interval of 0.12–0.20 sec, and a QRS of <0.12 sec. This is the baseline rhythm
against which all other rhythms are compared. It indicates that the SA node is correctly pacing the heart
with normal conduction.
2. A patient's heart rate is 140 beats/min with regular rhythm. The P wave is upright, PR interval 0.16
sec, and QRS duration 0.08 sec. The patient is anxious after a minor medical procedure. What is the
rhythm?
- A) Normal Sinus Rhythm
- B) Sinus Tachycardia
- C) Supraventricular Tachycardia
- D) Atrial Flutter
Answer: B
,Sinus Tachycardia originates from the SA node and is characterized by a rate greater than 100 bpm
(usually 100–150 bpm) with a regular rhythm, normal P wave morphology, and normal PR and QRS
intervals. Anxiety, exercise, and fever are common causes. The key distinction from more serious SVT is
(a) the presence of normal, upright P waves before each QRS and (b) a gradual onset/offset.
3. A patient’s rhythm strip has a heart rate of 48 bpm. The P waves are upright and precede every QRS.
The PR interval is normal at 0.18 sec. The QRS is narrow (<0.12 sec). What is the most likely rhythm?
- A) Normal Sinus Rhythm
- B) Sinus Bradycardia
- C) Sinus Arrest
- D) Junctional Rhythm
Answer: B
Sinus Bradycardia is defined as a sinus rhythm (upright P wave, normal conduction) with a rate below 60
bpm. In this case, with a rate of 48 bpm and normal P waves, it is sinus bradycardia. This rhythm is often
well tolerated in healthy individuals (e.g., athletes) but can cause symptoms in others due to decreased
cardiac output.
4. Which of the following is a characteristic of Sinus Arrhythmia?
- A) The rhythm is irregular, with the rate increasing during inspiration and decreasing during expiration
- B) P waves are absent
- C) The rhythm is regularly irregular with dropped QRS complexes
- D) The PR interval is prolonged and variable
Answer: A
Sinus arrhythmia is a variant of normal sinus rhythm where the heart rate varies with the respiratory
cycle. The HR increases during inspiration (due to decreased vagal tone) and decreases during
expiration. The rhythm is irregular, but the EKG morphology remains normal. This is most common in
young, healthy people and is generally benign.
5. A patient has a regular rhythm at a rate of 40 bpm. The P wave is upright and normal in shape. The PR
interval is 0.16 sec and QRS width is 0.08 sec. The patient is asymptomatic and has been a long-distance
runner for 20 years. What is the most appropriate action?
,- A) Prepare for temporary pacing
- B) Administer atropine 0.5 mg IV push
- C) Recognize this as a normal finding in an athletic heart and document
- D) Notify the physician for a stat cardiology consult
Answer: C
A heart rate of 40 bpm with sinus bradycardia in a well-conditioned athlete is likely a normal physiologic
adaptation. The patient’s asymptomatic status is key; no intervention is required. Treatment for sinus
bradycardia is only indicated if the patient is symptomatic (hypotension, chest pain, syncope, altered
mental status).
6. A patient’s heart rate is in the range of 110–120 bpm. The rhythm is regular. P waves are upright and
each is followed by a QRS. The QRS duration is <0.12 sec. The patient complains of palpitations after
drinking a large caffeinated soda. What is the rhythm?
- A) Sinus Tachycardia
- B) Atrial Fibrillation
- C) Ventricular Tachycardia
- D) Atrial Flutter
Answer: A
This describes Sinus Tachycardia. The SA node fires faster than 100 bpm in response to a physiologic
stressor (in this case, caffeine). The rhythm remains regular, and the conduction sequence is normal.
The patient is aware of palpitations, but the rhythm itself is benign and typically resolves with removal
of the stimulus.
7. You are reviewing a rhythm strip. The rate is 62 bpm, but the P waves are obscured by large T waves.
What six-second strip technique should you use to double-check the rate?
- A) Count the number of R waves in a 6-second strip and multiply by 10
- B) Divide 300 by the number of large boxes between R waves
- C) Count the number of P waves in a 6-second strip and multiply by 10
- D) Look at the QRS duration only
, Answer: A
The most accurate method for an irregular rhythm or when P waves are hard to see is the 6-second strip
method. You count the number of R waves in a 6-second strip (there are 30 large boxes or 3 seconds per
1-inch mark in standard recording). Multiply that count by 10 to get the rate. The 300 method (divide by
the number of large boxes between R waves) is only accurate for regular rhythms.
8. In Normal Sinus Rhythm, what is the correct duration for the PR interval?
- A) 0.20–0.40 seconds
- B) 0.12–0.20 seconds
- C) >0.20 seconds
- D) <0.10 seconds
Answer: B
The PR interval, measured from the onset of the P wave to the onset of the QRS complex, represents the
time for the impulse to travel from the SA node through the atria and the AV node, where it is delayed.
In a healthy conducting system, this takes 0.12–0.20 seconds (3–5 small boxes). A PR interval >0.20
seconds indicates a first-degree AV block.
9. Which lead is considered the "rhythm strip" most commonly used for telemetry monitoring?
- A) Lead aVL
- B) Lead V3
- C) Lead II
- D) Lead aVF
Answer: C
Lead II is the most frequently used lead for continuous telemetry and rhythm strips because it provides a
clear view of the P wave and aligns with the heart’s electrical axis. Long strips from Lead II are standard
for analyzing rhythm regularity.
10. An elderly patient is found to have a heart rate of 52 bpm. The EKG shows a regular rhythm with
upright P waves before each QRS, PR interval 0.18 sec, QRS 0.08 sec. The patient reports feeling tired
and lightheaded. Which of the following is the most appropriate initial intervention?
