CCDS IBHRE EXAM STUDY GUIDE 2026
COMPLETE QUESTIONS WITH CORRECT
DETAILED ANSWERS || 100% GUARANTEED
PASS <RECENT VERSION>
Section 1: Fundamentals of Electrophysiology and Sensing
1. What is the primary ionic current responsible for the Phase 0
depolarization in a ventricular myocyte?
A) Inward Calcium (I_Ca)
B) Inward Sodium (I_Na)
C) Outward Potassium (I_K)
D) Funny Current (I_f)
2. The absolute refractory period (ARP) in a cardiac cell is primarily
defined by the inactivation of which channels?
A) Potassium Channels
B) Sodium Channels
C) Calcium Channels
D) Chloride Channels
3. What is the standard sensitivity setting for a pacemaker to sense an R-
wave?
A) 0.5 - 1.0 mV
B) 2.0 - 3.0 mV
C) 5.0 - 6.0 mV
D) 10.0 - 12.0 mV
4. Oversensing occurs when:
A) The device fails to detect intrinsic cardiac activity.
B) The device detects non-physiological or unwanted signals as cardiac
events.
C) The pacing output is set too high.
D) The lead impedance is out of range.
, 5. A "safety pace" is delivered in which timing window of a dual-chamber
pacemaker?
A) Atrial Refractory Period
B) Ventricular Refractory Period
C) Non-physiologic AV Delay (also called the Crosstalk Detection Window)
D) Post-Ventricular Atrial Refractory Period (PVARP)
Section 2: Pacing Fundamentals and Modes
6. In pacemaker code NBG, what does the fourth letter "R" indicate?
A) Rate Smoothing
B) Rate Responsive Pacing
C) Reverse Mode Switch
D) Remote Monitoring
7. What is the primary purpose of the Post-Ventricular Atrial Refractory
Period (PVARP)?
A) To prevent atrial pacing during the ventricular refractory period.
B) To prevent sensing the far-field R-wave or retrograde P-wave as an
intrinsic atrial event.
C) To allow for rate-responsive sensor-driven pacing.
D) To define the maximum tracking rate.
8. In a DDD pacemaker, the Upper Tracking Rate (UTR) is limited by:
A) The Total Atrial Refractory Period (TARP)
B) The Atrioventricular (AV) Delay
C) The Lower Rate Limit (LRL)
D) The Ventricular Refractory Period
9. A patient with a VVI pacemaker at 60 ppm presents with a continuous
rhythm of intrinsic P-waves followed by paced QRS complexes at 50
bpm. This demonstrates:
A) Undersensing
B) Oversensing
, C) Failure to capture
D) Lack of atrial tracking (normal VVI behavior)
10.Which pacing mode is most appropriate for a patient with permanent
atrial fibrillation and symptomatic bradycardia?
A) AAIR
B) VVIR
C) DDD
D) DDDR
Section 3: Implantable Cardioveter Defibrillators (ICDs)
11.The primary purpose of a shocking coil in an ICD system is to:
A) Sense ventricular fibrillation.
B) Deliver high-energy therapy to terminate VF/VT.
C) Provide bradycardia pacing support.
D) Measure lead impedance.
12.What is the typical energy range for an ICD to defibrillate ventricular
fibrillation?
A) 0.5 - 5 Joules
B) 5 - 10 Joules
C) 15 - 40 Joules
D) 50 - 100 Joules
13.During capacitor charging in an ICD, what type of pacing is typically
provided?
A) Anti-tachycardia Pacing (ATP)
B) Asynchronous (non-sensing) pacing
C) Rate-responsive pacing
D) No pacing is delivered
14.A "committed" shock means that:
A) The shock can be aborted if the tachycardia terminates spontaneously.
B) The shock will be delivered regardless of the rhythm after charging is
complete.
COMPLETE QUESTIONS WITH CORRECT
DETAILED ANSWERS || 100% GUARANTEED
PASS <RECENT VERSION>
Section 1: Fundamentals of Electrophysiology and Sensing
1. What is the primary ionic current responsible for the Phase 0
depolarization in a ventricular myocyte?
A) Inward Calcium (I_Ca)
B) Inward Sodium (I_Na)
C) Outward Potassium (I_K)
D) Funny Current (I_f)
2. The absolute refractory period (ARP) in a cardiac cell is primarily
defined by the inactivation of which channels?
A) Potassium Channels
B) Sodium Channels
C) Calcium Channels
D) Chloride Channels
3. What is the standard sensitivity setting for a pacemaker to sense an R-
wave?
A) 0.5 - 1.0 mV
B) 2.0 - 3.0 mV
C) 5.0 - 6.0 mV
D) 10.0 - 12.0 mV
4. Oversensing occurs when:
A) The device fails to detect intrinsic cardiac activity.
B) The device detects non-physiological or unwanted signals as cardiac
events.
C) The pacing output is set too high.
D) The lead impedance is out of range.
, 5. A "safety pace" is delivered in which timing window of a dual-chamber
pacemaker?
A) Atrial Refractory Period
B) Ventricular Refractory Period
C) Non-physiologic AV Delay (also called the Crosstalk Detection Window)
D) Post-Ventricular Atrial Refractory Period (PVARP)
Section 2: Pacing Fundamentals and Modes
6. In pacemaker code NBG, what does the fourth letter "R" indicate?
A) Rate Smoothing
B) Rate Responsive Pacing
C) Reverse Mode Switch
D) Remote Monitoring
7. What is the primary purpose of the Post-Ventricular Atrial Refractory
Period (PVARP)?
A) To prevent atrial pacing during the ventricular refractory period.
B) To prevent sensing the far-field R-wave or retrograde P-wave as an
intrinsic atrial event.
C) To allow for rate-responsive sensor-driven pacing.
D) To define the maximum tracking rate.
8. In a DDD pacemaker, the Upper Tracking Rate (UTR) is limited by:
A) The Total Atrial Refractory Period (TARP)
B) The Atrioventricular (AV) Delay
C) The Lower Rate Limit (LRL)
D) The Ventricular Refractory Period
9. A patient with a VVI pacemaker at 60 ppm presents with a continuous
rhythm of intrinsic P-waves followed by paced QRS complexes at 50
bpm. This demonstrates:
A) Undersensing
B) Oversensing
, C) Failure to capture
D) Lack of atrial tracking (normal VVI behavior)
10.Which pacing mode is most appropriate for a patient with permanent
atrial fibrillation and symptomatic bradycardia?
A) AAIR
B) VVIR
C) DDD
D) DDDR
Section 3: Implantable Cardioveter Defibrillators (ICDs)
11.The primary purpose of a shocking coil in an ICD system is to:
A) Sense ventricular fibrillation.
B) Deliver high-energy therapy to terminate VF/VT.
C) Provide bradycardia pacing support.
D) Measure lead impedance.
12.What is the typical energy range for an ICD to defibrillate ventricular
fibrillation?
A) 0.5 - 5 Joules
B) 5 - 10 Joules
C) 15 - 40 Joules
D) 50 - 100 Joules
13.During capacitor charging in an ICD, what type of pacing is typically
provided?
A) Anti-tachycardia Pacing (ATP)
B) Asynchronous (non-sensing) pacing
C) Rate-responsive pacing
D) No pacing is delivered
14.A "committed" shock means that:
A) The shock can be aborted if the tachycardia terminates spontaneously.
B) The shock will be delivered regardless of the rhythm after charging is
complete.
