Relias Dysrhythmia Basic A Test –
2025/2026 – Complete Questions and
Correct Answers with Explanations
Relias Dysrhythmia Basic A – Practice
Questions
1. What is the normal heart rate for an adult at rest?
A. 40–60 bpm
B. 60–100 bpm
C. 100–120 bpm
D. 120–140 bpm
Answer: B
Explanation: The normal resting heart rate for adults is 60–100 beats per minute (bpm).
2. Which part of the ECG represents atrial depolarization?
A. P wave
B. QRS complex
C. T wave
D. PR interval
Answer: A
Explanation: The P wave corresponds to atrial depolarization.
,3. Which rhythm is characterized by a regular rate of
60–100 bpm, with normal P waves before each QRS
complex?
A. Sinus tachycardia
B. Sinus bradycardia
C. Normal sinus rhythm
D. Atrial fibrillation
Answer: C
Explanation: Normal sinus rhythm has a regular rate, with P waves preceding each QRS.
4. Sinus bradycardia is defined as:
A. Heart rate >100 bpm
B. Heart rate <60 bpm
C. Irregular rhythm
D. Absence of P waves
Answer: B
Explanation: Sinus bradycardia occurs when heart rate is less than 60 bpm with normal P
waves and rhythm.
5. Which dysrhythmia shows absent P waves, irregularly
irregular rhythm, and variable ventricular response?
A. Atrial flutter
B. Atrial fibrillation
C. Ventricular tachycardia
D. Sinus tachycardia
Answer: B
Explanation: Atrial fibrillation has no P waves and an irregularly irregular rhythm.
,6. Which dysrhythmia shows sawtooth-shaped P waves
with a regular atrial rate?
A. Atrial fibrillation
B. Atrial flutter
C. Ventricular fibrillation
D. Junctional rhythm
Answer: B
Explanation: Atrial flutter is identified by sawtooth flutter waves, often at 250–350 atrial
bpm.
7. What is the main risk associated with atrial fibrillation?
A. Bradycardia
B. Ventricular fibrillation
C. Stroke due to thrombus formation
D. Hyperkalemia
Answer: C
Explanation: Blood pooling in the atria can form clots, increasing stroke risk.
8. Which dysrhythmia shows wide QRS complexes, rapid
rate, and no P waves?
A. Ventricular tachycardia
B. Atrial flutter
C. Sinus tachycardia
D. First-degree AV block
Answer: A
Explanation: Ventricular tachycardia arises from ventricles and has wide QRS complexes,
often >100 bpm.
, 9. Which dysrhythmia is immediately life-threatening and
requires defibrillation?
A. Sinus tachycardia
B. Ventricular fibrillation
C. Atrial flutter
D. First-degree AV block
Answer: B
Explanation: Ventricular fibrillation causes no cardiac output and is fatal without prompt
defibrillation.
10. First-degree AV block is characterized by:
A. PR interval >0.20 seconds, constant for each beat
B. PR interval <0.12 seconds
C. Dropped QRS complexes
D. Irregularly irregular rhythm
Answer: A
Explanation: First-degree AV block shows prolonged PR interval but all atrial impulses
conduct to ventricles.
11. Second-degree AV block type I (Wenckebach) shows:
A. Progressive PR prolongation followed by dropped QRS
B. Randomly dropped QRS without PR prolongation
C. PR interval <0.12 seconds
D. Ventricular rate >150 bpm
Answer: A
Explanation: In Mobitz I, the PR interval lengthens progressively until a QRS is dropped.
12. Second-degree AV block type II is characterized by:
2025/2026 – Complete Questions and
Correct Answers with Explanations
Relias Dysrhythmia Basic A – Practice
Questions
1. What is the normal heart rate for an adult at rest?
A. 40–60 bpm
B. 60–100 bpm
C. 100–120 bpm
D. 120–140 bpm
Answer: B
Explanation: The normal resting heart rate for adults is 60–100 beats per minute (bpm).
2. Which part of the ECG represents atrial depolarization?
A. P wave
B. QRS complex
C. T wave
D. PR interval
Answer: A
Explanation: The P wave corresponds to atrial depolarization.
,3. Which rhythm is characterized by a regular rate of
60–100 bpm, with normal P waves before each QRS
complex?
A. Sinus tachycardia
B. Sinus bradycardia
C. Normal sinus rhythm
D. Atrial fibrillation
Answer: C
Explanation: Normal sinus rhythm has a regular rate, with P waves preceding each QRS.
4. Sinus bradycardia is defined as:
A. Heart rate >100 bpm
B. Heart rate <60 bpm
C. Irregular rhythm
D. Absence of P waves
Answer: B
Explanation: Sinus bradycardia occurs when heart rate is less than 60 bpm with normal P
waves and rhythm.
5. Which dysrhythmia shows absent P waves, irregularly
irregular rhythm, and variable ventricular response?
A. Atrial flutter
B. Atrial fibrillation
C. Ventricular tachycardia
D. Sinus tachycardia
Answer: B
Explanation: Atrial fibrillation has no P waves and an irregularly irregular rhythm.
,6. Which dysrhythmia shows sawtooth-shaped P waves
with a regular atrial rate?
A. Atrial fibrillation
B. Atrial flutter
C. Ventricular fibrillation
D. Junctional rhythm
Answer: B
Explanation: Atrial flutter is identified by sawtooth flutter waves, often at 250–350 atrial
bpm.
7. What is the main risk associated with atrial fibrillation?
A. Bradycardia
B. Ventricular fibrillation
C. Stroke due to thrombus formation
D. Hyperkalemia
Answer: C
Explanation: Blood pooling in the atria can form clots, increasing stroke risk.
8. Which dysrhythmia shows wide QRS complexes, rapid
rate, and no P waves?
A. Ventricular tachycardia
B. Atrial flutter
C. Sinus tachycardia
D. First-degree AV block
Answer: A
Explanation: Ventricular tachycardia arises from ventricles and has wide QRS complexes,
often >100 bpm.
, 9. Which dysrhythmia is immediately life-threatening and
requires defibrillation?
A. Sinus tachycardia
B. Ventricular fibrillation
C. Atrial flutter
D. First-degree AV block
Answer: B
Explanation: Ventricular fibrillation causes no cardiac output and is fatal without prompt
defibrillation.
10. First-degree AV block is characterized by:
A. PR interval >0.20 seconds, constant for each beat
B. PR interval <0.12 seconds
C. Dropped QRS complexes
D. Irregularly irregular rhythm
Answer: A
Explanation: First-degree AV block shows prolonged PR interval but all atrial impulses
conduct to ventricles.
11. Second-degree AV block type I (Wenckebach) shows:
A. Progressive PR prolongation followed by dropped QRS
B. Randomly dropped QRS without PR prolongation
C. PR interval <0.12 seconds
D. Ventricular rate >150 bpm
Answer: A
Explanation: In Mobitz I, the PR interval lengthens progressively until a QRS is dropped.
12. Second-degree AV block type II is characterized by:
