RELIAS DYSRHYTHMIA BASIC TEST
(REVISED VERSION) A+ GRADED|35
CORRECT VERIFIED QUESTIONS AND
ANSWERS
Basic Dysrhythmia Practice Examination
35 Questions with Answers and Detailed Rationales
Comprehensive Nursing Review — Original Practice Version
Instructions: Choose the one best answer for each question. This practice examination focuses
on rhythm recognition, ECG fundamentals, patient assessment, and initial nursing priorities.
Question 1
The nurse is reviewing a normal sinus rhythm (NSR). Which finding is expected?
A. Heart rate 40–60 beats/minute
B. Regular rhythm with a P wave before every QRS complex
C. No identifiable P waves
D. Wide QRS complexes greater than 0.12 seconds
Correct Answer: B
Rationale: Normal sinus rhythm originates in the sinoatrial (SA) node. It is characterized by a
regular rhythm, a rate generally between 60 and 100 beats/minute, a consistent P wave before
every QRS complex, and a narrow QRS complex.
Question 2
Which ECG component represents ventricular depolarization?
,A. P wave
B. PR interval
C. QRS complex
D. T wave
Correct Answer: C
Rationale: The QRS complex represents ventricular depolarization, which triggers ventricular
contraction. The P wave represents atrial depolarization, while the T wave represents ventricular
repolarization.
Question 3
The nurse measures a PR interval of 0.24 seconds. How should this finding be interpreted?
A. Normal
B. Prolonged
C. Shortened
D. Absent
Correct Answer: B
Rationale: A normal PR interval is approximately 0.12–0.20 seconds. A PR interval longer than
0.20 seconds indicates delayed conduction through the AV node and may be associated with
first-degree AV block.
Question 4
Which finding is most consistent with first-degree AV block?
A. PR interval greater than 0.20 seconds and consistent
B. Progressive PR prolongation followed by a dropped QRS
C. Completely unrelated P waves and QRS complexes
D. No P waves with an irregularly irregular rhythm
Correct Answer: A
Rationale: First-degree AV block is characterized by a prolonged PR interval greater than 0.20
seconds, with every P wave followed by a QRS complex.
, Question 5
A patient has an ECG showing progressively lengthening PR intervals followed by a dropped
QRS complex. Which rhythm is most likely?
A. First-degree AV block
B. Second-degree AV block, Mobitz I
C. Second-degree AV block, Mobitz II
D. Third-degree AV block
Correct Answer: B
Rationale: Mobitz I, also called Wenckebach, is characterized by progressive prolongation of
the PR interval until a QRS complex is dropped.
Question 6
Which ECG finding is characteristic of second-degree AV block, Mobitz II?
A. PR interval progressively lengthens before every dropped beat
B. Constant PR intervals with intermittent dropped QRS complexes
C. No relationship between P waves and QRS complexes
D. A narrow QRS with no P waves
Correct Answer: B
Rationale: Mobitz II typically demonstrates consistent PR intervals with sudden, intermittent
nonconducted P waves. This rhythm can progress to complete heart block and requires close
monitoring.
Question 7
The nurse is assessing a patient with third-degree AV block. Which finding is expected?
A. Every P wave is followed by a QRS complex
B. Progressive PR interval prolongation
C. Atrial and ventricular activity occur independently
D. The rhythm is always sinus tachycardia
Correct Answer: C
(REVISED VERSION) A+ GRADED|35
CORRECT VERIFIED QUESTIONS AND
ANSWERS
Basic Dysrhythmia Practice Examination
35 Questions with Answers and Detailed Rationales
Comprehensive Nursing Review — Original Practice Version
Instructions: Choose the one best answer for each question. This practice examination focuses
on rhythm recognition, ECG fundamentals, patient assessment, and initial nursing priorities.
Question 1
The nurse is reviewing a normal sinus rhythm (NSR). Which finding is expected?
A. Heart rate 40–60 beats/minute
B. Regular rhythm with a P wave before every QRS complex
C. No identifiable P waves
D. Wide QRS complexes greater than 0.12 seconds
Correct Answer: B
Rationale: Normal sinus rhythm originates in the sinoatrial (SA) node. It is characterized by a
regular rhythm, a rate generally between 60 and 100 beats/minute, a consistent P wave before
every QRS complex, and a narrow QRS complex.
Question 2
Which ECG component represents ventricular depolarization?
,A. P wave
B. PR interval
C. QRS complex
D. T wave
Correct Answer: C
Rationale: The QRS complex represents ventricular depolarization, which triggers ventricular
contraction. The P wave represents atrial depolarization, while the T wave represents ventricular
repolarization.
Question 3
The nurse measures a PR interval of 0.24 seconds. How should this finding be interpreted?
A. Normal
B. Prolonged
C. Shortened
D. Absent
Correct Answer: B
Rationale: A normal PR interval is approximately 0.12–0.20 seconds. A PR interval longer than
0.20 seconds indicates delayed conduction through the AV node and may be associated with
first-degree AV block.
Question 4
Which finding is most consistent with first-degree AV block?
A. PR interval greater than 0.20 seconds and consistent
B. Progressive PR prolongation followed by a dropped QRS
C. Completely unrelated P waves and QRS complexes
D. No P waves with an irregularly irregular rhythm
Correct Answer: A
Rationale: First-degree AV block is characterized by a prolonged PR interval greater than 0.20
seconds, with every P wave followed by a QRS complex.
, Question 5
A patient has an ECG showing progressively lengthening PR intervals followed by a dropped
QRS complex. Which rhythm is most likely?
A. First-degree AV block
B. Second-degree AV block, Mobitz I
C. Second-degree AV block, Mobitz II
D. Third-degree AV block
Correct Answer: B
Rationale: Mobitz I, also called Wenckebach, is characterized by progressive prolongation of
the PR interval until a QRS complex is dropped.
Question 6
Which ECG finding is characteristic of second-degree AV block, Mobitz II?
A. PR interval progressively lengthens before every dropped beat
B. Constant PR intervals with intermittent dropped QRS complexes
C. No relationship between P waves and QRS complexes
D. A narrow QRS with no P waves
Correct Answer: B
Rationale: Mobitz II typically demonstrates consistent PR intervals with sudden, intermittent
nonconducted P waves. This rhythm can progress to complete heart block and requires close
monitoring.
Question 7
The nurse is assessing a patient with third-degree AV block. Which finding is expected?
A. Every P wave is followed by a QRS complex
B. Progressive PR interval prolongation
C. Atrial and ventricular activity occur independently
D. The rhythm is always sinus tachycardia
Correct Answer: C
