ECG Analysis: Rhythm Recognition (Relias)
Exam Study Guide 2026/2027 | Verified
Questions & Answers | Cardiac Rhythm
Interpretation Certification Prep PDF
ECG ANALYSIS: RHYTHM RECOGNITION (RELIAS) EXAM STUDY GUIDE 2026/2027
DOCUMENT OVERVIEW
• This study guide contains 200 verified practice questions designed to strengthen
your cardiac rhythm interpretation skills and prepare you for the Relias ECG
Analysis certification exam with detailed clinical rationales.
• Study systematically through each question, focus on rhythm strips characteristics
(rate, regularity, P waves, PR interval, QRS duration), and use the rationales to build
pattern recognition for accurate real-world rhythm identification.
1. QUESTION
What is the normal heart rate range for sinus rhythm in an adult at rest?
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 resting adults ranges from 60-100 bpm. This
is the standard baseline for cardiac rhythm interpretation. Rates below 60 are
considered bradycardic, while rates above 100 are tachycardic. The 60-100 range
represents normal SA node firing frequency in healthy individuals.
2. QUESTION
Which of the following characteristics are present in normal sinus rhythm?
,A) Irregular rhythm with absent P waves
B) Regular rhythm with one P wave before each QRS complex
C) Regular rhythm with multiple P waves before each QRS
D) Irregular rhythm with uniform P waves
E) Regular rhythm with inverted P waves
✓ CORRECT ANSWER: B) Regular rhythm with one P wave before each QRS
complex
RATIONALE: Normal sinus rhythm demonstrates a regular rhythm with one upright
P wave preceding each QRS complex. The PR interval is consistent (0.12-0.20
seconds), and the QRS duration is normal (0.06-0.10 seconds). This pattern
indicates appropriate SA node function and AV conduction.
3. QUESTION
What does the PR interval represent on an ECG?
A) Time from P wave to R wave peak
B) Time for atrial depolarization
C) Time from atrial depolarization to ventricular depolarization initiation
D) Time for ventricular repolarization
E) Time between consecutive R waves
✓ CORRECT ANSWER: C) Time from atrial depolarization to ventricular
depolarization initiation
RATIONALE: The PR interval measures from the beginning of the P wave to the
beginning of the QRS complex, representing conduction through the atrium and AV
node. Normal PR interval is 0.12-0.20 seconds. This interval is critical for assessing
AV node function and conduction delays.
,4. QUESTION
A 65-year-old patient presents with a heart rate of 45 bpm with normal P
waves and QRS complexes. What rhythm is most likely?
A) Atrial fibrillation
B) Sinus bradycardia
C) Sinus arrest
D) First-degree AV block
E) Atrial flutter
✓ CORRECT ANSWER: B) Sinus bradycardia
RATIONALE: Sinus bradycardia is defined as normal sinus rhythm with a rate below
60 bpm. This patient has appropriate P waves and QRS complexes at a slow rate.
Sinus bradycardia can be normal in athletes or caused by medications,
hypothermia, or increased vagal tone.
5. QUESTION
What is the primary cause of a prolonged PR interval?
A) Increased atrial conduction velocity
B) Delayed conduction through the AV node
C) Increased ventricular depolarization
D) Decreased atrial depolarization
E) Rapid SA node firing
✓ CORRECT ANSWER: B) Delayed conduction through the AV node
RATIONALE: A prolonged PR interval (>0.20 seconds) indicates delayed AV nodal
conduction. This can result from AV node disease, medication effects (beta-
blockers, calcium channel blockers), ischemia, or electrolyte abnormalities. It
represents first-degree AV block when all impulses eventually conduct.
, 6. QUESTION
Which rhythm demonstrates an irregular pattern with a sawtooth baseline?
A) Atrial fibrillation
B) Atrial flutter
C) Sinus tachycardia
D) Ventricular fibrillation
E) Atrial tachycardia
✓ CORRECT ANSWER: B) Atrial flutter
RATIONALE: Atrial flutter is characterized by a regular or regular-to-irregular
ventricular rhythm with a distinctive sawtooth pattern in the baseline representing
rapid atrial depolarization (250-350 apm). Ventricular response depends on AV
nodal conduction ratio (2:1, 3:1, variable).
7. QUESTION
What is the typical atrial rate during atrial flutter?
A) 100-150 bpm
B) 150-200 bpm
C) 200-250 bpm
D) 250-350 bpm
E) 350-400 bpm
✓ CORRECT ANSWER: D) 250-350 bpm
RATIONALE: Atrial flutter typically has an atrial rate of 250-350 bpm, with typical
atrial flutter around 300 bpm. The ventricular response is usually slower due to
physiologic AV node refractoriness. The distinct atrial rate helps differentiate flutter
from other tachyarrhythmias.
Exam Study Guide 2026/2027 | Verified
Questions & Answers | Cardiac Rhythm
Interpretation Certification Prep PDF
ECG ANALYSIS: RHYTHM RECOGNITION (RELIAS) EXAM STUDY GUIDE 2026/2027
DOCUMENT OVERVIEW
• This study guide contains 200 verified practice questions designed to strengthen
your cardiac rhythm interpretation skills and prepare you for the Relias ECG
Analysis certification exam with detailed clinical rationales.
• Study systematically through each question, focus on rhythm strips characteristics
(rate, regularity, P waves, PR interval, QRS duration), and use the rationales to build
pattern recognition for accurate real-world rhythm identification.
1. QUESTION
What is the normal heart rate range for sinus rhythm in an adult at rest?
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 resting adults ranges from 60-100 bpm. This
is the standard baseline for cardiac rhythm interpretation. Rates below 60 are
considered bradycardic, while rates above 100 are tachycardic. The 60-100 range
represents normal SA node firing frequency in healthy individuals.
2. QUESTION
Which of the following characteristics are present in normal sinus rhythm?
,A) Irregular rhythm with absent P waves
B) Regular rhythm with one P wave before each QRS complex
C) Regular rhythm with multiple P waves before each QRS
D) Irregular rhythm with uniform P waves
E) Regular rhythm with inverted P waves
✓ CORRECT ANSWER: B) Regular rhythm with one P wave before each QRS
complex
RATIONALE: Normal sinus rhythm demonstrates a regular rhythm with one upright
P wave preceding each QRS complex. The PR interval is consistent (0.12-0.20
seconds), and the QRS duration is normal (0.06-0.10 seconds). This pattern
indicates appropriate SA node function and AV conduction.
3. QUESTION
What does the PR interval represent on an ECG?
A) Time from P wave to R wave peak
B) Time for atrial depolarization
C) Time from atrial depolarization to ventricular depolarization initiation
D) Time for ventricular repolarization
E) Time between consecutive R waves
✓ CORRECT ANSWER: C) Time from atrial depolarization to ventricular
depolarization initiation
RATIONALE: The PR interval measures from the beginning of the P wave to the
beginning of the QRS complex, representing conduction through the atrium and AV
node. Normal PR interval is 0.12-0.20 seconds. This interval is critical for assessing
AV node function and conduction delays.
,4. QUESTION
A 65-year-old patient presents with a heart rate of 45 bpm with normal P
waves and QRS complexes. What rhythm is most likely?
A) Atrial fibrillation
B) Sinus bradycardia
C) Sinus arrest
D) First-degree AV block
E) Atrial flutter
✓ CORRECT ANSWER: B) Sinus bradycardia
RATIONALE: Sinus bradycardia is defined as normal sinus rhythm with a rate below
60 bpm. This patient has appropriate P waves and QRS complexes at a slow rate.
Sinus bradycardia can be normal in athletes or caused by medications,
hypothermia, or increased vagal tone.
5. QUESTION
What is the primary cause of a prolonged PR interval?
A) Increased atrial conduction velocity
B) Delayed conduction through the AV node
C) Increased ventricular depolarization
D) Decreased atrial depolarization
E) Rapid SA node firing
✓ CORRECT ANSWER: B) Delayed conduction through the AV node
RATIONALE: A prolonged PR interval (>0.20 seconds) indicates delayed AV nodal
conduction. This can result from AV node disease, medication effects (beta-
blockers, calcium channel blockers), ischemia, or electrolyte abnormalities. It
represents first-degree AV block when all impulses eventually conduct.
, 6. QUESTION
Which rhythm demonstrates an irregular pattern with a sawtooth baseline?
A) Atrial fibrillation
B) Atrial flutter
C) Sinus tachycardia
D) Ventricular fibrillation
E) Atrial tachycardia
✓ CORRECT ANSWER: B) Atrial flutter
RATIONALE: Atrial flutter is characterized by a regular or regular-to-irregular
ventricular rhythm with a distinctive sawtooth pattern in the baseline representing
rapid atrial depolarization (250-350 apm). Ventricular response depends on AV
nodal conduction ratio (2:1, 3:1, variable).
7. QUESTION
What is the typical atrial rate during atrial flutter?
A) 100-150 bpm
B) 150-200 bpm
C) 200-250 bpm
D) 250-350 bpm
E) 350-400 bpm
✓ CORRECT ANSWER: D) 250-350 bpm
RATIONALE: Atrial flutter typically has an atrial rate of 250-350 bpm, with typical
atrial flutter around 300 bpm. The ventricular response is usually slower due to
physiologic AV node refractoriness. The distinct atrial rate helps differentiate flutter
from other tachyarrhythmias.
