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
An ECG rhythm shows a regular rate of 72 bpm, each QRS
complex is preceded by a uniform upright P wave, PR interval is
0.16 seconds, and QRS duration is 0.08 seconds. Which
structure is 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 ECG shows normal sinus rhythm: regular rate (60–100
bpm), upright P waves before each QRS, normal PR (0.12–0.20
sec), and narrow QRS. This indicates impulse origin from the SA
node, the heart’s natural pacemaker.
• A: AV node would produce slower rates (40–60 bpm).
• C & D: These are ventricular conduction pathways, not
primary pacemakers.
Source:
ECG Workout: Exercises in Arrhythmia Interpretation, 8th
Edition – Chapter 1
Question 2
An ECG tracing shows absence of P waves before QRS
complexes, a rate of 48 bpm, and regular rhythm. Which part of
the cardiac conduction system is most likely controlling this
rhythm?
A. SA node
B. Atria
C. AV junction
D. Ventricles
Correct Answer: C
Rationale:
A rate of 40–60 bpm with absent or inverted P waves suggests
a junctional rhythm originating from the AV junction.
, • A: SA node rhythms include visible P waves.
• B: Atrial rhythms typically show abnormal P waves.
• D: Ventricular rhythms have wide QRS complexes.
Source:
ECG Workout: Exercises in Arrhythmia Interpretation, 8th
Edition – Chapter 1
Question 3
An ECG demonstrates a rate of 110 bpm, regular rhythm,
upright P waves before each QRS, PR interval 0.14 seconds. This
rhythm indicates increased stimulation of which system
affecting cardiac innervation?
A. Parasympathetic nervous system
B. Sympathetic nervous system
C. Coronary arteries
D. Pulmonary circulation
Correct Answer: B
Rationale:
Sinus tachycardia (>100 bpm) is caused by increased
sympathetic stimulation, which increases heart rate.
• A: Parasympathetic slows heart rate.
• C & D: These affect blood flow, not rate control directly.
Source:
ECG Workout: Exercises in Arrhythmia Interpretation, 8th
Edition – Chapter 1