Relias Dysrhythmia Basic A & B 2026–2027 |
Exam Questions and Correct Answers | ECG
Interpretation and Cardiac Rhythm Analysis
RELIAS DYSRHYTHMIA BASIC A & B 2026–2027 EXAM
DOCUMENT OVERVIEW
• Comprehensive 200-question study material covering ECG interpretation,
cardiac rhythm analysis, dysrhythmia identification, and clinical nursing
management of arrhythmias
• Self-paced learning tool designed for certification preparation—review each
question thoroughly, check your answer, and use the detailed rationales to master
dysrhythmia concepts and clinical decision-making
QUESTIONS 1–25: BASIC ECG INTERPRETATION AND NORMAL SINUS RHYTHM
1. What is the normal heart rate range for an adult in normal sinus rhythm?
A) 40–60 beats per minute
B) 60–100 beats per minute
C) 100–120 beats per minute
D) 120–140 beats per minute
E) 140–160 beats per minute
✓ CORRECT ANSWER: B) 60–100 beats per minute
RATIONALE: Normal sinus rhythm in adults is defined as a heart rate between 60
and 100 beats per minute. Rates below 60 are considered bradycardic, and rates
above 100 are tachycardic. This is the standard reference range taught in all cardiac
care and nursing education programs.
2. Which component of the ECG represents ventricular depolarization?
,A) P wave
B) QRS complex
C) T wave
D) PR interval
E) ST segment
✓ CORRECT ANSWER: B) QRS complex
RATIONALE: The QRS complex represents the depolarization of the ventricles. The P
wave represents atrial depolarization, the T wave represents ventricular
repolarization, the PR interval is the time from atrial depolarization to ventricular
depolarization, and the ST segment is the period between the end of ventricular
depolarization and the beginning of ventricular repolarization.
3. What is the normal duration of the PR interval?
A) 0.04–0.08 seconds
B) 0.08–0.12 seconds
C) 0.12–0.20 seconds
D) 0.20–0.28 seconds
E) 0.28–0.36 seconds
✓ CORRECT ANSWER: C) 0.12–0.20 seconds
RATIONALE: The PR interval normally measures 0.12 to 0.20 seconds (3 to 5 small
squares on standard ECG paper). This interval represents the time from the
beginning of atrial depolarization (P wave) to the beginning of ventricular
depolarization (QRS complex). Prolongation of this interval may indicate
atrioventricular (AV) block.
4. Which of the following is a characteristic feature of normal sinus rhythm?
,A) P wave before each QRS complex with a constant PR interval
B) Regular rhythm with variable P waves
C) Absent P waves before QRS complexes
D) Multiple P waves before each QRS
E) Inverted P waves in all leads
✓ CORRECT ANSWER: A) P wave before each QRS complex with a constant PR
interval
RATIONALE: In normal sinus rhythm, each atrial depolarization (P wave) is followed
by a QRS complex, and the PR interval remains consistent. This constant
relationship between the P wave and QRS complex is essential for normal sinus
rhythm. Variable PR intervals or missing P waves would indicate dysrhythmia.
5. What is the normal duration of the QRS complex?
A) 0.04–0.06 seconds
B) 0.06–0.10 seconds
C) 0.10–0.12 seconds
D) 0.12–0.16 seconds
E) 0.16–0.20 seconds
✓ CORRECT ANSWER: C) 0.10–0.12 seconds
RATIONALE: The normal QRS complex duration is 0.10 seconds or less (2.5 small
squares or less on standard ECG paper). A QRS duration greater than 0.12 seconds
(3 small squares) indicates a wide QRS complex and may suggest ventricular
conduction delay or ectopic ventricular activity.
6. Which wave on the ECG represents atrial repolarization?
A) P wave
, B) QRS complex
C) T wave
D) U wave
E) Not visible; typically buried in the QRS or T wave
✓ CORRECT ANSWER: E) Not visible; typically buried in the QRS or T wave
RATIONALE: Atrial repolarization typically occurs during ventricular depolarization
(QRS complex) and is not visible as a distinct wave on the ECG because it is buried
within the QRS complex. The T wave visible on the ECG represents ventricular
repolarization, not atrial repolarization.
7. What is the normal duration of the QT interval at a heart rate of 60–80
bpm?
A) 0.20–0.28 seconds
B) 0.28–0.36 seconds
C) 0.36–0.44 seconds
D) 0.44–0.52 seconds
E) 0.52–0.60 seconds
✓ CORRECT ANSWER: C) 0.36–0.44 seconds
RATIONALE: The normal QT interval is approximately 0.36 to 0.44 seconds at
normal heart rates (60–80 bpm). The QT interval varies with heart rate; it shortens
with faster rates and lengthens with slower rates. A prolonged QT interval increases
the risk of torsades de pointes, a dangerous ventricular dysrhythmia.
8. Which of the following accurately describes the relationship between heart
rate and PR interval?
A) Heart rate has no effect on PR interval duration
Exam Questions and Correct Answers | ECG
Interpretation and Cardiac Rhythm Analysis
RELIAS DYSRHYTHMIA BASIC A & B 2026–2027 EXAM
DOCUMENT OVERVIEW
• Comprehensive 200-question study material covering ECG interpretation,
cardiac rhythm analysis, dysrhythmia identification, and clinical nursing
management of arrhythmias
• Self-paced learning tool designed for certification preparation—review each
question thoroughly, check your answer, and use the detailed rationales to master
dysrhythmia concepts and clinical decision-making
QUESTIONS 1–25: BASIC ECG INTERPRETATION AND NORMAL SINUS RHYTHM
1. What is the normal heart rate range for an adult in normal sinus rhythm?
A) 40–60 beats per minute
B) 60–100 beats per minute
C) 100–120 beats per minute
D) 120–140 beats per minute
E) 140–160 beats per minute
✓ CORRECT ANSWER: B) 60–100 beats per minute
RATIONALE: Normal sinus rhythm in adults is defined as a heart rate between 60
and 100 beats per minute. Rates below 60 are considered bradycardic, and rates
above 100 are tachycardic. This is the standard reference range taught in all cardiac
care and nursing education programs.
2. Which component of the ECG represents ventricular depolarization?
,A) P wave
B) QRS complex
C) T wave
D) PR interval
E) ST segment
✓ CORRECT ANSWER: B) QRS complex
RATIONALE: The QRS complex represents the depolarization of the ventricles. The P
wave represents atrial depolarization, the T wave represents ventricular
repolarization, the PR interval is the time from atrial depolarization to ventricular
depolarization, and the ST segment is the period between the end of ventricular
depolarization and the beginning of ventricular repolarization.
3. What is the normal duration of the PR interval?
A) 0.04–0.08 seconds
B) 0.08–0.12 seconds
C) 0.12–0.20 seconds
D) 0.20–0.28 seconds
E) 0.28–0.36 seconds
✓ CORRECT ANSWER: C) 0.12–0.20 seconds
RATIONALE: The PR interval normally measures 0.12 to 0.20 seconds (3 to 5 small
squares on standard ECG paper). This interval represents the time from the
beginning of atrial depolarization (P wave) to the beginning of ventricular
depolarization (QRS complex). Prolongation of this interval may indicate
atrioventricular (AV) block.
4. Which of the following is a characteristic feature of normal sinus rhythm?
,A) P wave before each QRS complex with a constant PR interval
B) Regular rhythm with variable P waves
C) Absent P waves before QRS complexes
D) Multiple P waves before each QRS
E) Inverted P waves in all leads
✓ CORRECT ANSWER: A) P wave before each QRS complex with a constant PR
interval
RATIONALE: In normal sinus rhythm, each atrial depolarization (P wave) is followed
by a QRS complex, and the PR interval remains consistent. This constant
relationship between the P wave and QRS complex is essential for normal sinus
rhythm. Variable PR intervals or missing P waves would indicate dysrhythmia.
5. What is the normal duration of the QRS complex?
A) 0.04–0.06 seconds
B) 0.06–0.10 seconds
C) 0.10–0.12 seconds
D) 0.12–0.16 seconds
E) 0.16–0.20 seconds
✓ CORRECT ANSWER: C) 0.10–0.12 seconds
RATIONALE: The normal QRS complex duration is 0.10 seconds or less (2.5 small
squares or less on standard ECG paper). A QRS duration greater than 0.12 seconds
(3 small squares) indicates a wide QRS complex and may suggest ventricular
conduction delay or ectopic ventricular activity.
6. Which wave on the ECG represents atrial repolarization?
A) P wave
, B) QRS complex
C) T wave
D) U wave
E) Not visible; typically buried in the QRS or T wave
✓ CORRECT ANSWER: E) Not visible; typically buried in the QRS or T wave
RATIONALE: Atrial repolarization typically occurs during ventricular depolarization
(QRS complex) and is not visible as a distinct wave on the ECG because it is buried
within the QRS complex. The T wave visible on the ECG represents ventricular
repolarization, not atrial repolarization.
7. What is the normal duration of the QT interval at a heart rate of 60–80
bpm?
A) 0.20–0.28 seconds
B) 0.28–0.36 seconds
C) 0.36–0.44 seconds
D) 0.44–0.52 seconds
E) 0.52–0.60 seconds
✓ CORRECT ANSWER: C) 0.36–0.44 seconds
RATIONALE: The normal QT interval is approximately 0.36 to 0.44 seconds at
normal heart rates (60–80 bpm). The QT interval varies with heart rate; it shortens
with faster rates and lengthens with slower rates. A prolonged QT interval increases
the risk of torsades de pointes, a dangerous ventricular dysrhythmia.
8. Which of the following accurately describes the relationship between heart
rate and PR interval?
A) Heart rate has no effect on PR interval duration
