ECG Workout
Exercises in Arrhythmia Interpretation
8th Edition
Author(s)Jane Huff
,TEST BANK
Table of Contents — ECG Workout: Exercises in Arrhythmia Interpretation, 8th Edition
1. Anatomy and Physiology of the Heart
2. Electrophysiology
3. Waveforms, Complexes, Intervals, and Segments
4. Cardiac Monitors
5. Analyzing a Rhythm Strip
6. Sinus Rhythms
7. Atrial Rhythms
8. Junctional Rhythms and AV Blocks
9. Ventricular Rhythms and Bundle-Branch Block
10. Pacemakers
11. Posttes
Question 1
A patient’s ECG shows a regular rhythm at 72 bpm with upright
P waves preceding each QRS complex and a consistent PR
interval. Which cardiac structure is primarily responsible for
initiating this rhythm?
A. Atrioventricular (AV) node
B. Sinoatrial (SA) node
C. Bundle of His
D. Purkinje fibers
,Correct Answer: B
Rationale:
The SA node is the heart’s primary pacemaker and initiates
normal sinus rhythm. The ECG shows normal sinus
characteristics: regular rate (60–100 bpm), upright P waves,
and consistent PR interval.
• A is incorrect: AV node delays conduction but does not
initiate normal sinus rhythm.
• C and D are conduction pathways, not primary pacemakers
under normal conditions.
Source: ECG Workout: Exercises in Arrhythmia Interpretation,
8th Edition – Chapter 1
Question 2
An ECG shows delayed ventricular depolarization with a
prolonged PR interval but normal P waves and QRS complexes.
Which physiological function of the AV node explains this
finding?
A. Rapid impulse conduction
B. Electrical impulse initiation
C. Conduction delay between atria and ventricles
D. Ventricular repolarization
Correct Answer: C
, Rationale:
The AV node slows conduction to allow ventricular filling before
contraction. This delay is reflected in the PR interval.
• A is incorrect: AV node conduction is intentionally slow.
• B is incorrect: SA node initiates impulses.
• D relates to T wave, not AV node function.
Source: ECG Workout: Exercises in Arrhythmia Interpretation,
8th Edition – Chapter 1
Question 3
A patient’s ECG demonstrates normal atrial depolarization
followed by ventricular depolarization. Which pathway
correctly represents the electrical conduction from atria to
ventricles?
A. SA node → Purkinje fibers → AV node → Bundle branches
B. SA node → AV node → Bundle of His → Bundle branches →
Purkinje fibers
C. AV node → SA node → Bundle branches → Purkinje fibers
D. Purkinje fibers → Bundle of His → AV node → SA node
Correct Answer: B
Rationale:
Normal conduction follows: SA node → AV node → Bundle of
His → bundle branches → Purkinje fibers. This sequence
ensures coordinated contraction.
Exercises in Arrhythmia Interpretation
8th Edition
Author(s)Jane Huff
,TEST BANK
Table of Contents — ECG Workout: Exercises in Arrhythmia Interpretation, 8th Edition
1. Anatomy and Physiology of the Heart
2. Electrophysiology
3. Waveforms, Complexes, Intervals, and Segments
4. Cardiac Monitors
5. Analyzing a Rhythm Strip
6. Sinus Rhythms
7. Atrial Rhythms
8. Junctional Rhythms and AV Blocks
9. Ventricular Rhythms and Bundle-Branch Block
10. Pacemakers
11. Posttes
Question 1
A patient’s ECG shows a regular rhythm at 72 bpm with upright
P waves preceding each QRS complex and a consistent PR
interval. Which cardiac structure is primarily responsible for
initiating this rhythm?
A. Atrioventricular (AV) node
B. Sinoatrial (SA) node
C. Bundle of His
D. Purkinje fibers
,Correct Answer: B
Rationale:
The SA node is the heart’s primary pacemaker and initiates
normal sinus rhythm. The ECG shows normal sinus
characteristics: regular rate (60–100 bpm), upright P waves,
and consistent PR interval.
• A is incorrect: AV node delays conduction but does not
initiate normal sinus rhythm.
• C and D are conduction pathways, not primary pacemakers
under normal conditions.
Source: ECG Workout: Exercises in Arrhythmia Interpretation,
8th Edition – Chapter 1
Question 2
An ECG shows delayed ventricular depolarization with a
prolonged PR interval but normal P waves and QRS complexes.
Which physiological function of the AV node explains this
finding?
A. Rapid impulse conduction
B. Electrical impulse initiation
C. Conduction delay between atria and ventricles
D. Ventricular repolarization
Correct Answer: C
, Rationale:
The AV node slows conduction to allow ventricular filling before
contraction. This delay is reflected in the PR interval.
• A is incorrect: AV node conduction is intentionally slow.
• B is incorrect: SA node initiates impulses.
• D relates to T wave, not AV node function.
Source: ECG Workout: Exercises in Arrhythmia Interpretation,
8th Edition – Chapter 1
Question 3
A patient’s ECG demonstrates normal atrial depolarization
followed by ventricular depolarization. Which pathway
correctly represents the electrical conduction from atria to
ventricles?
A. SA node → Purkinje fibers → AV node → Bundle branches
B. SA node → AV node → Bundle of His → Bundle branches →
Purkinje fibers
C. AV node → SA node → Bundle branches → Purkinje fibers
D. Purkinje fibers → Bundle of His → AV node → SA node
Correct Answer: B
Rationale:
Normal conduction follows: SA node → AV node → Bundle of
His → bundle branches → Purkinje fibers. This sequence
ensures coordinated contraction.
