Certification Exam Practice Questions

Cardiac Electrophysiology Specialist Certification Exam Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

1. The primary pacemaker of the heart is located in the:

• AV node
• Bundle of His
• SA node
• Purkinje fibers

Answer: SA node

Rationale: The sinoatrial (SA) node initiates the electrical impulses in the

heart and sets the normal heart rate.

2. A normal PR interval on ECG ranges from:

• 0.04–0.08 sec 1 / 4

• 0.12–0.20 sec
• 0.20–0.30 sec
• 0.30–0.40 sec

Answer: 0.12–0.20 sec

Rationale: The PR interval represents atrial depolarization and AV node

conduction. A normal interval is 120–200 milliseconds.

3. The most common cause of sudden cardiac death in adults is:

• Bradycardia
• Ventricular fibrillation
• Atrial flutter
• Heart block

Answer: Ventricular fibrillation

Rationale: Ventricular fibrillation is a life-threatening arrhythmia that leads

to loss of cardiac output and is the most common cause of sudden cardiac death.

• Which antiarrhythmic drug class primarily blocks sodium channels?
• Class II
• Class I
• Class III
• Class IV 2 / 4

Answer: Class I

Rationale: Class I antiarrhythmics block fast sodium channels, slowing

conduction in the atria, ventricles, and His-Purkinje system.

5. The term “torsades de pointes” refers to:

• Atrial tachycardia
• Polymorphic ventricular tachycardia
• AV block
• Sinus bradycardia

Answer: Polymorphic ventricular tachycardia

Rationale: Torsades de pointes is a form of polymorphic ventricular

tachycardia associated with prolonged QT interval.

• Which electrolyte disturbance most commonly precipitates torsades

de pointes?

• Hypernatremia
• Hypomagnesemia
• Hypercalcemia
• Hypokalemia

Answer: Hypomagnesemia

Rationale: Low magnesium levels destabilize myocardial cells and can

trigger torsades de pointes.

• The most appropriate treatment for stable supraventricular

tachycardia is: 3 / 4

• Immediate defibrillation
• Vagal maneuvers
• Epinephrine
• Amiodarone

Answer: Vagal maneuvers

Rationale: Vagal maneuvers increase parasympathetic tone, slowing AV

node conduction and potentially terminating SVT.

• In Wolff-Parkinson-White (WPW) syndrome, the characteristic ECG

finding is:

• Wide QRS with delta wave
• ST-segment elevation
• Short PR interval with delta wave
• Prolonged QT interval

Answer: Short PR interval with delta wave

Rationale: WPW syndrome shows pre-excitation due to an accessory

pathway, leading to a short PR interval and slurred QRS upstroke (delta wave).

• Which drug is first-line for acute management of ventricular

tachycardia with a pulse?

• Lidocaine
• Amiodarone
• Verapamil
• Adenosine
• / 4