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IBHRE CCDS Exam 2026-2027 BANK QUESTIONS WITH
DETAILED VERIFIED ANSWERS EXAM QUESTIONS
WILL COME FROM HERE (100% Latest Already Graded
A+
QUESTION 1
A 72-year-old male with ischemic cardiomyopathy and an ICD presents
for routine follow-up. Interrogation reveals frequent episodes of
nonsustained ventricular tachycardia. The device is programmed with
three zones: VF zone 200 bpm, VT-1 zone 170 bpm, and VT-2 zone 150
bpm. Which of the following programming adjustments would MOST
effectively reduce inappropriate therapy while maintaining safety?
A) Increase the VT-1 detection interval to 24 cycles
B) Decrease the VF detection rate to 180 bpm
C) Enable supraventricular tachycardia discriminators in the VT-2 zone
only
D) Program antitachycardia pacing in the VF zone
Answer: A
Explanation: Increasing detection intervals requires more consecutive
beats to satisfy detection, which reduces inappropriate therapy for self-
terminating arrhythmias. Option B would make VF detection more
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sensitive, potentially increasing inappropriate shocks. Option C is
insufficient as discriminators should be enabled in all VT zones. Option D
is contraindicated as ATP in VF zone is typically not recommended due
to the rapid rate and hemodynamic instability.
QUESTION 2
A patient with a dual-chamber pacemaker programmed DDD 60-130
bpm presents with symptoms of lightheadedness. The
electrocardiogram shows ventricular pacing at 130 bpm with 1:1
ventriculoatrial conduction. The most likely diagnosis is:
A) Pacemaker-mediated tachycardia
B) Sensor-driven tachycardia
C) Atrial tachyarrhythmia
D) Ventricular tachycardia
Answer: A
Explanation: Pacemaker-mediated tachycardia (PMT) occurs when
ventricular paced beats conduct retrogradely to the atrium, are sensed,
and trigger ventricular pacing after the programmed AV interval. The
upper rate limit of 130 bpm and 1:1 VA conduction are classic features.
Sensor-driven tachycardia would not necessarily show 1:1 VA
conduction. The rate is too slow for ventricular tachycardia in this
context.
QUESTION 3
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Which of the following best describes the function of the automatic
gain control in an implantable cardioverter-defibrillator sensing circuit?
A) It maintains constant sensitivity regardless of signal amplitude
B) It adjusts the sensitivity threshold based on the amplitude of sensed
signals
C) It filters out high-frequency noise from the electromagnetic
interference
D) It regulates the pacing output based on the impedance
Answer: B
Explanation: Automatic gain control dynamically adjusts the sensitivity
threshold in response to the amplitude of sensed intracardiac signals.
When signals are large, the threshold increases; when signals are small,
the threshold decreases. This prevents oversensing of large signals and
undersensing of small signals. Option A is incorrect because sensitivity is
not constant. Option C describes filtering, not gain control. Option D
describes output regulation.
QUESTION 4
A 65-year-old female with nonischemic cardiomyopathy and a CRT-D
device is seen for routine follow-up. Device interrogation reveals that
92% of ventricular beats are paced. The QRS duration on the surface
ECG is 148 ms. Which of the following interventions would MOST likely
improve the percentage of biventricular pacing?
A) Decrease the programmed AV delay
B) Increase the lower rate limit
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C) Program the ventricular pacing mode to VVI
D) Decrease the upper rate limit
Answer: A
Explanation: Decreasing the programmed AV delay allows more
ventricular pacing by shortening the time available for intrinsic
conduction, thereby promoting biventricular capture. Option B
increasing the lower rate limit may increase pacing but does not
specifically address fusion/pseudofusion issues. Option C would
eliminate atrial sensing and is not appropriate for CRT. Option D does
not directly affect percentage of biventricular pacing at rest.
QUESTION 5
During a device interrogation, you note that the ventricular lead
impedance has decreased from 600 ohms to 350 ohms since the last
follow-up. The pacing threshold has increased from 0.8 V to 2.5 V at 0.4
ms. The most appropriate next step is:
A) Increase the pacing output to 5.0 V
B) Obtain a chest radiograph to evaluate lead integrity
C) Reprogram the pacing mode to VVI
D) Schedule a lead revision
Answer: B
Explanation: A significant decrease in impedance with a concurrent
increase in threshold suggests a lead insulation breach or conductor
IBHRE CCDS Exam 2026-2027 BANK QUESTIONS WITH
DETAILED VERIFIED ANSWERS EXAM QUESTIONS
WILL COME FROM HERE (100% Latest Already Graded
A+
QUESTION 1
A 72-year-old male with ischemic cardiomyopathy and an ICD presents
for routine follow-up. Interrogation reveals frequent episodes of
nonsustained ventricular tachycardia. The device is programmed with
three zones: VF zone 200 bpm, VT-1 zone 170 bpm, and VT-2 zone 150
bpm. Which of the following programming adjustments would MOST
effectively reduce inappropriate therapy while maintaining safety?
A) Increase the VT-1 detection interval to 24 cycles
B) Decrease the VF detection rate to 180 bpm
C) Enable supraventricular tachycardia discriminators in the VT-2 zone
only
D) Program antitachycardia pacing in the VF zone
Answer: A
Explanation: Increasing detection intervals requires more consecutive
beats to satisfy detection, which reduces inappropriate therapy for self-
terminating arrhythmias. Option B would make VF detection more
,2|Page
sensitive, potentially increasing inappropriate shocks. Option C is
insufficient as discriminators should be enabled in all VT zones. Option D
is contraindicated as ATP in VF zone is typically not recommended due
to the rapid rate and hemodynamic instability.
QUESTION 2
A patient with a dual-chamber pacemaker programmed DDD 60-130
bpm presents with symptoms of lightheadedness. The
electrocardiogram shows ventricular pacing at 130 bpm with 1:1
ventriculoatrial conduction. The most likely diagnosis is:
A) Pacemaker-mediated tachycardia
B) Sensor-driven tachycardia
C) Atrial tachyarrhythmia
D) Ventricular tachycardia
Answer: A
Explanation: Pacemaker-mediated tachycardia (PMT) occurs when
ventricular paced beats conduct retrogradely to the atrium, are sensed,
and trigger ventricular pacing after the programmed AV interval. The
upper rate limit of 130 bpm and 1:1 VA conduction are classic features.
Sensor-driven tachycardia would not necessarily show 1:1 VA
conduction. The rate is too slow for ventricular tachycardia in this
context.
QUESTION 3
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Which of the following best describes the function of the automatic
gain control in an implantable cardioverter-defibrillator sensing circuit?
A) It maintains constant sensitivity regardless of signal amplitude
B) It adjusts the sensitivity threshold based on the amplitude of sensed
signals
C) It filters out high-frequency noise from the electromagnetic
interference
D) It regulates the pacing output based on the impedance
Answer: B
Explanation: Automatic gain control dynamically adjusts the sensitivity
threshold in response to the amplitude of sensed intracardiac signals.
When signals are large, the threshold increases; when signals are small,
the threshold decreases. This prevents oversensing of large signals and
undersensing of small signals. Option A is incorrect because sensitivity is
not constant. Option C describes filtering, not gain control. Option D
describes output regulation.
QUESTION 4
A 65-year-old female with nonischemic cardiomyopathy and a CRT-D
device is seen for routine follow-up. Device interrogation reveals that
92% of ventricular beats are paced. The QRS duration on the surface
ECG is 148 ms. Which of the following interventions would MOST likely
improve the percentage of biventricular pacing?
A) Decrease the programmed AV delay
B) Increase the lower rate limit
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C) Program the ventricular pacing mode to VVI
D) Decrease the upper rate limit
Answer: A
Explanation: Decreasing the programmed AV delay allows more
ventricular pacing by shortening the time available for intrinsic
conduction, thereby promoting biventricular capture. Option B
increasing the lower rate limit may increase pacing but does not
specifically address fusion/pseudofusion issues. Option C would
eliminate atrial sensing and is not appropriate for CRT. Option D does
not directly affect percentage of biventricular pacing at rest.
QUESTION 5
During a device interrogation, you note that the ventricular lead
impedance has decreased from 600 ohms to 350 ohms since the last
follow-up. The pacing threshold has increased from 0.8 V to 2.5 V at 0.4
ms. The most appropriate next step is:
A) Increase the pacing output to 5.0 V
B) Obtain a chest radiograph to evaluate lead integrity
C) Reprogram the pacing mode to VVI
D) Schedule a lead revision
Answer: B
Explanation: A significant decrease in impedance with a concurrent
increase in threshold suggests a lead insulation breach or conductor
