RELIAS Dysrhythmia Basic B Exam (2025/2026 Edition)
Total: 35 Questions | Verified with Correct Answers and
Rationales
1. The SA node is located in which part of the heart?
A. Left atrium
B. Right atrium
C. Left ventricle
D. Right ventricle
✅ Answer: B. Right atrium
Rationale: The sinoatrial (SA) node is the heart’s natural pacemaker located in the right atrium near the
superior vena cava.
2. The normal PR interval is:
A. 0.08–0.10 seconds
B. 0.12–0.20 seconds
C. 0.20–0.24 seconds
D. 0.24–0.30 seconds
✅ Answer: B. 0.12–0.20 seconds
Rationale: The PR interval represents atrial depolarization and conduction through the AV node.
3. The normal QRS duration is:
A. 0.04–0.08 seconds
B. 0.06–0.10 seconds
C. 0.10–0.12 seconds
D. 0.12–0.16 seconds
✅ Answer: B. 0.06–0.10 seconds
Rationale: The QRS complex represents ventricular depolarization; longer durations indicate
intraventricular conduction delays.
4. A rhythm that has a regular R–R interval of 0.8 seconds has what rate?
A. 60 bpm
B. 75 bpm
C. 80 bpm
D. 90 bpm
, ✅ Answer: B. 75 bpm
Rationale: 60 seconds ÷ 0.8 = 75 bpm.
5. Which rhythm originates in the AV node with absent or inverted P waves?
A. Atrial flutter
B. Junctional rhythm
C. Sinus bradycardia
D. Sinus rhythm
✅ Answer: B. Junctional rhythm
Rationale: The impulse originates in or near the AV node, causing retrograde or hidden P waves.
6. Atrial flutter has a characteristic appearance of:
A. Irregular baseline
B. F waves or “sawtooth” pattern
C. No P waves
D. Wide QRS complexes
✅ Answer: B. F waves or “sawtooth” pattern
Rationale: Atrial flutter produces uniform flutter waves at 250–350 bpm.
7. Ventricular fibrillation is best described as:
A. Rapid, irregular atrial activity
B. Chaotic ventricular activity with no pulse
C. Organized ventricular depolarization
D. Atrial contraction without QRS
✅ Answer: B. Chaotic ventricular activity with no pulse
Rationale: VFib is life-threatening and requires immediate defibrillation.
8. In sinus bradycardia, the heart rate is:
A. <60 bpm
B. 60–100 bpm
C. 100–150 bpm
D. >150 bpm
✅ Answer: A. <60 bpm
Rationale: Bradycardia indicates a slower than normal sinus rhythm.
9. A patient in asystole requires which intervention first?
Total: 35 Questions | Verified with Correct Answers and
Rationales
1. The SA node is located in which part of the heart?
A. Left atrium
B. Right atrium
C. Left ventricle
D. Right ventricle
✅ Answer: B. Right atrium
Rationale: The sinoatrial (SA) node is the heart’s natural pacemaker located in the right atrium near the
superior vena cava.
2. The normal PR interval is:
A. 0.08–0.10 seconds
B. 0.12–0.20 seconds
C. 0.20–0.24 seconds
D. 0.24–0.30 seconds
✅ Answer: B. 0.12–0.20 seconds
Rationale: The PR interval represents atrial depolarization and conduction through the AV node.
3. The normal QRS duration is:
A. 0.04–0.08 seconds
B. 0.06–0.10 seconds
C. 0.10–0.12 seconds
D. 0.12–0.16 seconds
✅ Answer: B. 0.06–0.10 seconds
Rationale: The QRS complex represents ventricular depolarization; longer durations indicate
intraventricular conduction delays.
4. A rhythm that has a regular R–R interval of 0.8 seconds has what rate?
A. 60 bpm
B. 75 bpm
C. 80 bpm
D. 90 bpm
, ✅ Answer: B. 75 bpm
Rationale: 60 seconds ÷ 0.8 = 75 bpm.
5. Which rhythm originates in the AV node with absent or inverted P waves?
A. Atrial flutter
B. Junctional rhythm
C. Sinus bradycardia
D. Sinus rhythm
✅ Answer: B. Junctional rhythm
Rationale: The impulse originates in or near the AV node, causing retrograde or hidden P waves.
6. Atrial flutter has a characteristic appearance of:
A. Irregular baseline
B. F waves or “sawtooth” pattern
C. No P waves
D. Wide QRS complexes
✅ Answer: B. F waves or “sawtooth” pattern
Rationale: Atrial flutter produces uniform flutter waves at 250–350 bpm.
7. Ventricular fibrillation is best described as:
A. Rapid, irregular atrial activity
B. Chaotic ventricular activity with no pulse
C. Organized ventricular depolarization
D. Atrial contraction without QRS
✅ Answer: B. Chaotic ventricular activity with no pulse
Rationale: VFib is life-threatening and requires immediate defibrillation.
8. In sinus bradycardia, the heart rate is:
A. <60 bpm
B. 60–100 bpm
C. 100–150 bpm
D. >150 bpm
✅ Answer: A. <60 bpm
Rationale: Bradycardia indicates a slower than normal sinus rhythm.
9. A patient in asystole requires which intervention first?
