Basic Arrhythmia Sentara Final Exam Questions and Verified Answers with Rationale Latest Edition 2026/2027

Basic Arrhythmia Sentara Final Exam
Questions and Verified Answers with
Rationale Latest Edition 2026/2027
Question 1
Which of the following is considered the primary pacemaker of
a normal, healthy human heart?
 A Atrioventricular node
 B Sinoatrial node
 C Bundle of His
 D Purkinje fiber network
Correct Answer: B
Rationale: The sinoatrial node is located in the upper wall of
the right atrium and possesses the fastest intrinsic firing rate,
making it the dominant natural pacemaker of the heart under
normal physiological conditions.
Question 2
What is the normal expected duration range for a healthy adult
PR interval?
 A 0.04 to 0.08 seconds
 B 0.12 to 0.20 seconds
 C 0.22 to 0.30 seconds
 D 0.35 to 0.50 seconds
Correct Answer: B

,Rationale: The PR interval represents the time required for an
electrical impulse to travel from the sinoatrial node through the
atria and the atrioventricular node into the ventricles, normally
measuring between 0.12 and 0.20 seconds.
Question 3
Which rhythm strip finding is characterized by an irregularly
irregular ventricular response, a wavy baseline, and a complete
absence of distinct P waves?
 A Atrial flutter
 B Sinus arrhythmia
 C Atrial fibrillation
 D Multifocal atrial tachycardia
Correct Answer: C
Rationale: Atrial fibrillation features chaotic, uncoordinated
electrical activity in the atria, resulting in an irregularly irregular
heartbeat, undulating baseline fibrillatory waves, and no true P
waves.
Question 4
What is the defining feature of a second-degree atrioventricular
block Type 2, also known as Mobitz Type 2?
 A Progressive lengthening of the PR interval until a QRS
complex is dropped
 B Constant PR intervals on all conducted beats with
intermittent, sudden dropped QRS complexes

,  C Complete independence between P waves and QRS
complexes
 D PR intervals measuring less than 0.10 seconds with wide
QRS complexes
Correct Answer: B
Rationale: Second-degree atrioventricular block Type 2 is
characterized by constant, unchanging PR intervals for all
conducted beats followed by sudden, unexpected non-conducted
P waves and dropped QRS complexes.
Question 5
Which lethal arrhythmia is identified by a completely chaotic,
irregular baseline with no discernible waves, complexes, or
mechanical cardiac output?
 A Ventricular tachycardia
 B Asystole
 C Ventricular fibrillation
 D Idioventricular rhythm
Correct Answer: C
Rationale: Ventricular fibrillation is a fatal cardiac arrest
rhythm where the ventricles quiver haphazardly without
generating any organized electrical complexes or effective blood
flow.
Question 6
What is the correct calculation method for determining the heart
rate of a regular rhythm using the large box method?

,  A Divide 1500 by the number of small boxes between two
consecutive R waves
 B Divide 300 by the number of large boxes between two
consecutive R waves
 C Multiply the number of R waves in a six-second strip by
10
 D Count the total number of P waves in one minute and
divide by two
Correct Answer: B
Rationale: The large box method divides the constant 300 by
the number of large squares separating consecutive R waves,
corresponding to rates of 300, 150, 100, 75, 60, and 50 beats per
minute.
Question 7
Which medication is the primary first-line pharmacological
treatment for symptomatic sinus bradycardia?
 A Amiodarone
 B Adenosine
 C Atropine
 D Epinephrine
Correct Answer: C
Rationale: Atropine is an anticholinergic drug that blocks vagal
nerve input to the sinoatrial node, effectively increasing the
heart rate in symptomatic bradycardia.
Question 8