Page 1 of 158
RELIAS DYSRHYTHMIA BASIC A PREP
WITH VERIFIED ANSWERS AND DETAILED
ACADEMIC YEAR | ALIGNED WITH LATEST
TABLE OF CONTENTS
| Section | Topic | Questions |
|---------|-------|-----------|
| **SECTION 1** | ECG Fundamentals and Cardiac Conduction | 1–30 |
| **SECTION 2** | Normal Sinus Rhythm and Sinus Dysrhythmias | 31–65 |
| **SECTION 3** | Atrial Dysrhythmias | 66–100 |
| **SECTION 4** | Junctional Dysrhythmias | 101–125 |
| **SECTION 5** | Ventricular Dysrhythmias | 126–165 |
| **SECTION 6** | Atrioventricular Heart Blocks | 166–200 |
| **SECTION 7** | Pacemaker Rhythms and Artificial Pacing | 201–220 |
| **SECTION 8** | Clinical Scenarios and Emergency Interventions | 221–250+ |
, Page 2 of 158
SECTION 1: ECG FUNDAMENTALS AND CARDIAC CONDUCTION
Questions 1–30
**Question 1**
The electrical impulse normally originates from which structure of the heart?
A) AV node
B) Bundle of His
C) SA node
D) Purkinje fibers
**Correct Answer: C) SA node**
**Rationale:** The sinoatrial (SA) node, located in the upper wall of the right atrium near the
opening of the superior vena cava, is the heart's natural pacemaker. It normally discharges at 60–
100 beats per minute. The AV node delays impulses to allow ventricular filling, the Bundle of
His conducts impulses from the AV node to the ventricles, and Purkinje fibers are the terminal
conduction pathway that distributes the impulse throughout the ventricles.
---
**Question 2**
At what rate does the SA node normally fire in a resting adult?
A) 20–40 beats per minute
B) 40–60 beats per minute
C) 60–100 beats per minute
D) 100–150 beats per minute
, Page 3 of 158
**Correct Answer: C) 60–100 beats per minute**
**Rationale:** The SA node is the primary pacemaker with an intrinsic firing rate of 60–100
bpm. The AV junction has a backup rate of 40–60 bpm, and the Purkinje fibers have an intrinsic
rate of 20–40 bpm. Understanding these backup pacemaker rates is essential for identifying
escape rhythms.
---
**Question 3**
Which component of the ECG represents ventricular depolarization?
A) P wave
B) PR interval
C) QRS complex
D) T wave
**Correct Answer: C) QRS complex**
**Rationale:** The QRS complex represents the electrical impulse traveling through the
ventricles, causing them to contract (ventricular depolarization). The P wave represents atrial
depolarization, and the T wave represents ventricular repolarization. The PR interval represents
the time from the onset of atrial depolarization to the onset of ventricular depolarization.
---
**Question 4**
, Page 4 of 158
On standard ECG paper, what does the horizontal axis measure?
A) Voltage
B) Time
C) Amplitude
D) Resistance
**Correct Answer: B) Time**
**Rationale:** The horizontal axis on ECG paper measures time. Standard ECG paper runs at
25 mm/second, with each small box representing 0.04 seconds and each large box representing
0.20 seconds. The vertical axis measures voltage (amplitude) in millivolts.
---
**Question 5**
What is the duration of one small box on standard ECG paper?
A) 0.04 seconds
B) 0.20 seconds
C) 0.10 seconds
D) 0.01 seconds
**Correct Answer: A) 0.04 seconds**
RELIAS DYSRHYTHMIA BASIC A PREP
WITH VERIFIED ANSWERS AND DETAILED
ACADEMIC YEAR | ALIGNED WITH LATEST
TABLE OF CONTENTS
| Section | Topic | Questions |
|---------|-------|-----------|
| **SECTION 1** | ECG Fundamentals and Cardiac Conduction | 1–30 |
| **SECTION 2** | Normal Sinus Rhythm and Sinus Dysrhythmias | 31–65 |
| **SECTION 3** | Atrial Dysrhythmias | 66–100 |
| **SECTION 4** | Junctional Dysrhythmias | 101–125 |
| **SECTION 5** | Ventricular Dysrhythmias | 126–165 |
| **SECTION 6** | Atrioventricular Heart Blocks | 166–200 |
| **SECTION 7** | Pacemaker Rhythms and Artificial Pacing | 201–220 |
| **SECTION 8** | Clinical Scenarios and Emergency Interventions | 221–250+ |
, Page 2 of 158
SECTION 1: ECG FUNDAMENTALS AND CARDIAC CONDUCTION
Questions 1–30
**Question 1**
The electrical impulse normally originates from which structure of the heart?
A) AV node
B) Bundle of His
C) SA node
D) Purkinje fibers
**Correct Answer: C) SA node**
**Rationale:** The sinoatrial (SA) node, located in the upper wall of the right atrium near the
opening of the superior vena cava, is the heart's natural pacemaker. It normally discharges at 60–
100 beats per minute. The AV node delays impulses to allow ventricular filling, the Bundle of
His conducts impulses from the AV node to the ventricles, and Purkinje fibers are the terminal
conduction pathway that distributes the impulse throughout the ventricles.
---
**Question 2**
At what rate does the SA node normally fire in a resting adult?
A) 20–40 beats per minute
B) 40–60 beats per minute
C) 60–100 beats per minute
D) 100–150 beats per minute
, Page 3 of 158
**Correct Answer: C) 60–100 beats per minute**
**Rationale:** The SA node is the primary pacemaker with an intrinsic firing rate of 60–100
bpm. The AV junction has a backup rate of 40–60 bpm, and the Purkinje fibers have an intrinsic
rate of 20–40 bpm. Understanding these backup pacemaker rates is essential for identifying
escape rhythms.
---
**Question 3**
Which component of the ECG represents ventricular depolarization?
A) P wave
B) PR interval
C) QRS complex
D) T wave
**Correct Answer: C) QRS complex**
**Rationale:** The QRS complex represents the electrical impulse traveling through the
ventricles, causing them to contract (ventricular depolarization). The P wave represents atrial
depolarization, and the T wave represents ventricular repolarization. The PR interval represents
the time from the onset of atrial depolarization to the onset of ventricular depolarization.
---
**Question 4**
, Page 4 of 158
On standard ECG paper, what does the horizontal axis measure?
A) Voltage
B) Time
C) Amplitude
D) Resistance
**Correct Answer: B) Time**
**Rationale:** The horizontal axis on ECG paper measures time. Standard ECG paper runs at
25 mm/second, with each small box representing 0.04 seconds and each large box representing
0.20 seconds. The vertical axis measures voltage (amplitude) in millivolts.
---
**Question 5**
What is the duration of one small box on standard ECG paper?
A) 0.04 seconds
B) 0.20 seconds
C) 0.10 seconds
D) 0.01 seconds
**Correct Answer: A) 0.04 seconds**
