ADVANCED DYSRHYTHMIA FINAL
EXAM MASTERY QUESTIONS AND
ANSWERS
1. Which characteristic most accurately distinguishes a Second-Degree AV Block Type II
(Mobitz II) from a Second-Degree AV Block Type I (Wenckebach)?
A. A constant PR interval in conducted beats with intermittent non-conducted P waves.
B. The presence of a progressively lengthening PR interval before a dropped QRS.
C. A total dissociation between the atria and the ventricles.
D. The absence of P waves preceding the QRS complexes.
Answer: A
Conceptual Explanation: In Mobitz II, the PR interval remains constant for all conducted
beats, whereas in Wenckebach, the PR interval lengthens progressively until a beat is
dropped.
2. When analyzing a rhythm strip, you note a wide QRS complex (>0.12s) and an RSR’ pattern
in lead V1. Which condition is most likely present?
A. Right Bundle Branch Block (RBBB)
,B. Left Bundle Branch Block (LBBB)
C. Wolff-Parkinson-White Syndrome
D. Ventricular Tachycardia
Answer: A
Conceptual Explanation: An RSR’ (rabbit ears) pattern in the right precordial leads
(V1/V2) with a widened QRS is a hallmark of Right Bundle Branch Block.
3. What is the primary physiological purpose of the AV node delay?
A. To increase the heart rate during exercise.
B. To allow time for the ventricles to fill completely (atrial kick).
C. To prevent the ventricles from contracting too slowly.
D. To synchronize the contraction of both atria.
Answer: B
Conceptual Explanation: The delay at the AV node allows the atria to finish contracting
and empty their blood into the ventricles before ventricular systole begins.
4. A patient presents with a regular rhythm, a rate of 160 bpm, no visible P waves, and a
narrow QRS. The patient is hemodynamically stable but symptomatic. What is the first-line
pharmacological intervention?
A. Amiodarone 150 mg IV push
B. Atropine 1 mg IV push
, C. Adenosine 6 mg rapid IV push
D. Epinephrine 1 mg IV push
Answer: C
Conceptual Explanation: For stable Supraventricular Tachycardia (SVT), Adenosine is the
first-line medication to attempt rhythm conversion.
5. Which of the following ECG findings is most indicative of hyperkalemia?
A. Prominent U waves
B. ST-segment depression
C. Shortened PR interval
D. Tall, peaked T waves
Answer: D
Conceptual Explanation: Hyperkalemia typically causes tall, narrow, ‘tented’ or peaked T
waves, followed by PR prolongation and QRS widening as levels rise.
6. In a Junctional Escape Rhythm, the P wave is most likely to be:
A. Upright and preceding every QRS.
B. Sawtooth in appearance.
C. Wide and notched.
D. Inverted, hidden, or appearing after the QRS.
EXAM MASTERY QUESTIONS AND
ANSWERS
1. Which characteristic most accurately distinguishes a Second-Degree AV Block Type II
(Mobitz II) from a Second-Degree AV Block Type I (Wenckebach)?
A. A constant PR interval in conducted beats with intermittent non-conducted P waves.
B. The presence of a progressively lengthening PR interval before a dropped QRS.
C. A total dissociation between the atria and the ventricles.
D. The absence of P waves preceding the QRS complexes.
Answer: A
Conceptual Explanation: In Mobitz II, the PR interval remains constant for all conducted
beats, whereas in Wenckebach, the PR interval lengthens progressively until a beat is
dropped.
2. When analyzing a rhythm strip, you note a wide QRS complex (>0.12s) and an RSR’ pattern
in lead V1. Which condition is most likely present?
A. Right Bundle Branch Block (RBBB)
,B. Left Bundle Branch Block (LBBB)
C. Wolff-Parkinson-White Syndrome
D. Ventricular Tachycardia
Answer: A
Conceptual Explanation: An RSR’ (rabbit ears) pattern in the right precordial leads
(V1/V2) with a widened QRS is a hallmark of Right Bundle Branch Block.
3. What is the primary physiological purpose of the AV node delay?
A. To increase the heart rate during exercise.
B. To allow time for the ventricles to fill completely (atrial kick).
C. To prevent the ventricles from contracting too slowly.
D. To synchronize the contraction of both atria.
Answer: B
Conceptual Explanation: The delay at the AV node allows the atria to finish contracting
and empty their blood into the ventricles before ventricular systole begins.
4. A patient presents with a regular rhythm, a rate of 160 bpm, no visible P waves, and a
narrow QRS. The patient is hemodynamically stable but symptomatic. What is the first-line
pharmacological intervention?
A. Amiodarone 150 mg IV push
B. Atropine 1 mg IV push
, C. Adenosine 6 mg rapid IV push
D. Epinephrine 1 mg IV push
Answer: C
Conceptual Explanation: For stable Supraventricular Tachycardia (SVT), Adenosine is the
first-line medication to attempt rhythm conversion.
5. Which of the following ECG findings is most indicative of hyperkalemia?
A. Prominent U waves
B. ST-segment depression
C. Shortened PR interval
D. Tall, peaked T waves
Answer: D
Conceptual Explanation: Hyperkalemia typically causes tall, narrow, ‘tented’ or peaked T
waves, followed by PR prolongation and QRS widening as levels rise.
6. In a Junctional Escape Rhythm, the P wave is most likely to be:
A. Upright and preceding every QRS.
B. Sawtooth in appearance.
C. Wide and notched.
D. Inverted, hidden, or appearing after the QRS.