IBHRE CEPS FINAL EXAM 2026–2027 STUDY GUIDE | COMPLETE PRACTICE QUESTIONS, ANSWERS & ELECTROPHYSIOLOGY CERTIFICATION REVIEW FOR CERTIFIED ELECTROPHYSIOLOGY SPECIALIST (CEPS)

IBHRE CEPS FINAL EXAM 2026–2027 STUDY
GUIDE | COMPLETE PRACTICE QUESTIONS,
ANSWERS & ELECTROPHYSIOLOGY
CERTIFICATION REVIEW FOR CERTIFIED
ELECTROPHYSIOLOGY SPECIALIST (CEPS)
• This practice exam contains 200 multiple-choice questions covering the full scope
of the IBHRE CEPS certification exam — use it to self-test, identify weak areas, and
reinforce core electrophysiology concepts.

• Each question includes five answer options (A–E), a clearly marked correct answer
with bold highlighting, and a EXPERT RATIONALE to deepen your understanding of
the reasoning behind each answer.



IBHRE CEPS FINAL EXAM 2026–2027 COMPLETE PRACTICE QUESTIONS &
ELECTROPHYSIOLOGY CERTIFICATION REVIEW



QUESTION 1

Which ion is primarily responsible for the rapid depolarization phase (Phase 0)
of the cardiac action potential in ventricular myocytes?

A. Potassium (K⁺)

B. Calcium (Ca²⁺)

C. Chloride (Cl⁻)

D. Magnesium (Mg²⁺)

E. Sodium (Na⁺)

Correct Answer: E. Sodium (Na⁺)

EXPERT RATIONALE: Phase 0 of the ventricular action potential is caused by the
rapid influx of sodium ions through fast voltage-gated Na⁺ channels, producing the
steep upstroke of depolarization.

,QUESTION 2

Which phase of the cardiac action potential represents the plateau phase?

A. Phase 0

B. Phase 1

C. Phase 2

D. Phase 3

E. Phase 4

Correct Answer: C. Phase 2

EXPERT RATIONALE: Phase 2 is the plateau phase, maintained primarily by a
balance between inward calcium current (L-type Ca²⁺ channels) and outward
potassium current, sustaining the action potential duration and allowing complete
ventricular contraction.



QUESTION 3

What is the normal PR interval on a surface ECG?

A. 60–80 ms

B. 80–100 ms

C. 120–200 ms

D. 200–240 ms

E. 240–300 ms

Correct Answer: C. 120–200 ms

EXPERT RATIONALE: The normal PR interval ranges from 120 to 200 ms (3–5 small
squares), representing the time from atrial depolarization through the AV node to
the onset of ventricular depolarization.

,QUESTION 4

In the His-Purkinje system, which structure divides into the right and left
bundle branches?

A. SA node

B. AV node

C. Bachmann's bundle

D. Bundle of His

E. Moderator band

Correct Answer: D. Bundle of His

EXPERT RATIONALE: The Bundle of His (common bundle) originates at the AV node
and divides into the right and left bundle branches, which then carry electrical
impulses rapidly to the ventricular myocardium.



QUESTION 5

Which of the following best describes automaticity in cardiac cells?

A. The ability of cells to conduct impulses rapidly

B. The property of cells to contract when stimulated

C. The resistance of cells to external electrical stimulation

D. The ability of cells to spontaneously depolarize

E. The property of cells to repolarize after stimulation

Correct Answer: D. The ability of cells to spontaneously depolarize

EXPERT RATIONALE: Automaticity is the intrinsic ability of certain cardiac cells (SA
node, AV node, His-Purkinje) to spontaneously depolarize to threshold and
generate an action potential without external stimulation.

, QUESTION 6

What is the intrinsic rate of the AV node pacemaker cells?

A. 60–100 bpm

B. 40–60 bpm

C. 20–40 bpm

D. 100–120 bpm

E. 15–25 bpm

Correct Answer: B. 40–60 bpm

EXPERT RATIONALE: The AV node has an intrinsic firing rate of 40–60 bpm, slower
than the SA node (60–100 bpm), making it a subsidiary pacemaker that takes over
only when SA node function is suppressed.



QUESTION 7

The Wolff-Parkinson-White (WPW) syndrome involves which abnormal
structure?

A. Mahaim fiber

B. James fiber

C. Accessory pathway (Bundle of Kent)

D. Internodal tract

E. Left posterior fascicle

Correct Answer: C. Accessory pathway (Bundle of Kent)

EXPERT RATIONALE: WPW syndrome is caused by an accessory pathway (Bundle of
Kent) that bypasses the AV node, producing ventricular pre-excitation, a delta wave,
short PR interval, and widened QRS on ECG.