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 consistent PR
intervals. 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 intervals.
• A is incorrect: AV node delays conduction but does not
initiate normal rhythm.
• C and D are conduction pathways, not primary
pacemakers.
Source: ECG Workout: Exercises in Arrhythmia Interpretation,
8th Edition – Chapter 1
Question 2
An ECG rhythm strip demonstrates normal sinus rhythm. Which
sequence correctly represents the flow of electrical conduction
through the heart?
A. AV node → SA node → ventricles → atria
B. SA node → atria → AV node → ventricles
C. Ventricles → AV node → SA node → atria
D. Purkinje fibers → SA node → AV node → atria
Correct Answer: B
Rationale:
Normal conduction begins at the SA node, spreads through the
atria, pauses at the AV node, and then travels to the ventricles.
, This sequence produces the P wave (atrial depolarization)
followed by the QRS complex (ventricular depolarization).
• Other options incorrectly sequence conduction.
Source: ECG Workout: Exercises in Arrhythmia Interpretation,
8th Edition – Chapter 1
Question 3
A patient’s ECG shows absent P waves with a regular ventricular
rhythm. Which structure may be acting as the pacemaker
instead of the SA node?
A. Left ventricle
B. AV junction
C. Coronary arteries
D. Aortic valve
Correct Answer: B
Rationale:
When P waves are absent, another pacemaker (often the AV
junction) may take over. This reflects a disruption in normal SA
node function.
• A is incorrect: ventricles do not typically initiate organized
rhythms unless escape rhythms occur.
• C and D are not involved in electrical conduction.
Source: ECG Workout: Exercises in Arrhythmia Interpretation,
8th Edition – Chapter 1
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 consistent PR
intervals. 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 intervals.
• A is incorrect: AV node delays conduction but does not
initiate normal rhythm.
• C and D are conduction pathways, not primary
pacemakers.
Source: ECG Workout: Exercises in Arrhythmia Interpretation,
8th Edition – Chapter 1
Question 2
An ECG rhythm strip demonstrates normal sinus rhythm. Which
sequence correctly represents the flow of electrical conduction
through the heart?
A. AV node → SA node → ventricles → atria
B. SA node → atria → AV node → ventricles
C. Ventricles → AV node → SA node → atria
D. Purkinje fibers → SA node → AV node → atria
Correct Answer: B
Rationale:
Normal conduction begins at the SA node, spreads through the
atria, pauses at the AV node, and then travels to the ventricles.
, This sequence produces the P wave (atrial depolarization)
followed by the QRS complex (ventricular depolarization).
• Other options incorrectly sequence conduction.
Source: ECG Workout: Exercises in Arrhythmia Interpretation,
8th Edition – Chapter 1
Question 3
A patient’s ECG shows absent P waves with a regular ventricular
rhythm. Which structure may be acting as the pacemaker
instead of the SA node?
A. Left ventricle
B. AV junction
C. Coronary arteries
D. Aortic valve
Correct Answer: B
Rationale:
When P waves are absent, another pacemaker (often the AV
junction) may take over. This reflects a disruption in normal SA
node function.
• A is incorrect: ventricles do not typically initiate organized
rhythms unless escape rhythms occur.
• C and D are not involved in electrical conduction.
Source: ECG Workout: Exercises in Arrhythmia Interpretation,
8th Edition – Chapter 1
