CCDS IBHRE EXAM QUESTIONS AND ANSWERS LATEST
UPDATE 2024/2025 ALL ANSWERS 100% CORRECT
VERIFIED BEST EXAM SOLUTION GRADED A+ FOR
SUCCESS
Rheobase - CORRECT ANSWERS the lowest point on a strength duration curve at an infinitely long
pulse duration
Chronaxie time - CORRECT ANSWERS the pulse width at twice the rheobase value. It approximates
the most efficient stimulation pulse duration
Charge (formula) - CORRECT ANSWERS Charge= I(current) x T(time)
Furman's formula - CORRECT ANSWERS Energy(microjoules)= I(current)xV(voltage)xT(pulse width)
Ohms law formula - CORRECT ANSWERS Voltage(electromotive force)= I(current/flow of electrons) x
R(resistance to current flow in ohms)
Functional Refractory Period - CORRECT ANSWERS the coupling interval which first results in a
measurable degree of delay in impulse conduction
Effective Refractory Period - CORRECT ANSWERS the longest coupling interval to be associated with
block
Devices with NO interaction with pacers - CORRECT ANSWERS 1. microwave oven, 2. CT
scan/Ultrasound 3. X-rays (diagnostic)
Devices that cause transient or 1 beat inhibition - CORRECT ANSWERS 1. EAS 2. Cellphones 3. Arc
Welding 4. airport metal detector 5. TENS 6. Electric appliances such as electric blanket & power
tools
Devices that may damage the pacemaker - CORRECT ANSWERS 1. MRI 2. Defibrillator 3.
Cardioversion 4. Cautery/RF Ablation 5. Radiation Therapy
Resistance in Series - CORRECT ANSWERS Series means the beginning of one resistance is connected
to another
,CCDS IBHRE EXAM QUESTIONS AND ANSWERS LATEST
UPDATE 2024/2025 ALL ANSWERS 100% CORRECT
VERIFIED BEST EXAM SOLUTION GRADED A+ FOR
SUCCESS
Sum the resistances: R1+R2= total resistance. EX: A LEAD FRACTURE (fractures INCREASE impedance)
Resistance in Parallel - CORRECT ANSWERS Parallel means all the resistances are connected to the
same point.
(R1xR2)/(R1+R2)= total resistance
EX: LEAD INSULATION DEFECTS (insulation defects DECREASE impedance)
Permanent pacemakers are constant voltage or constant current? - CORRECT ANSWERS ALL
permanent pacemakers are constant voltage devices.
SOME temp pacemakers are constant voltage, most are constant current.
LOAD - CORRECT ANSWERS Load refers to impedance (or resistance) applied to a circuit.
A system with a SMALL load (low impedance) applied to the circuit is said to be a constant current
device
A system with LARGE load is said to be a constant voltage device
Guidelines for Permanent Pacing - CORRECT ANSWERS 1. Patient is symptomatic
2. The heart rate is less than 40 bpm
3. Asystole of greater than 3 seconds is documented
NOTE: Pt may be asymptomatic with 2 or 3
Slew Rate - CORRECT ANSWERS Slew rate = peak slope of an electrogram
,CCDS IBHRE EXAM QUESTIONS AND ANSWERS LATEST
UPDATE 2024/2025 ALL ANSWERS 100% CORRECT
VERIFIED BEST EXAM SOLUTION GRADED A+ FOR
SUCCESS
slew rate= change in voltage/ change in time
Normal slew rate in atrium - CORRECT ANSWERS >.3 V/s
Normal slew rate in ventricle - CORRECT ANSWERS >.5V/s
Steroid used in electrodes - CORRECT ANSWERS dexamethasone sodium phosphate in the silicone
core(a corticosteriod)
Steroid-Eluting Electrodes - CORRECT ANSWERS 1. The acute threshold is relatively flat compared to
non-steroid electrodes
2. The initial capture threshold is similar to non-steroid leads
Silicone Rubber lead insulation Pros - CORRECT ANSWERS 1. Can easily be repaired
2. Flexible
3. Proven performance history
4. Easy to make
Silicone Rubber lead insulation cons - CORRECT ANSWERS 1. high friction coefficient
2. Absorbs lipids
3. More thrombogenic and fibrotic
4. Cuts easily
5. Tears easily if suture tied too tightly
6. Large diameter
Polyurethane 80A - CORRECT ANSWERS BAD
Polyurethane 55D - CORRECT ANSWERS GOOD
, CCDS IBHRE EXAM QUESTIONS AND ANSWERS LATEST
UPDATE 2024/2025 ALL ANSWERS 100% CORRECT
VERIFIED BEST EXAM SOLUTION GRADED A+ FOR
SUCCESS
polyurethane lead insulation pros - CORRECT ANSWERS 1. relatively nonthrombogenic/fibrotic
2. thin walls
3. high tear friction
4. resists cutting
5. low friction coefficient
polyurethane lead insulation cons - CORRECT ANSWERS 1. cannot be repaired
2. relatively stiff
3. hard to make
Pacemaker Syndrome Causes - CORRECT ANSWERS 1. Loss of AV synchrony
2. Sustained retrograde conduction
3. A single ventricular rate when rate modulation is required for exercise
Approx 25% of patients only paced from the ventricle may have some level of severity related to
pacemaker syndrome
Pacemaker syndrome diagnosis - CORRECT ANSWERS 1. Observe fluctuation in the peripheral blood
pressure
2. Cannon "A" wave in the neck
3. History alone
Pacemaker syndrome management - CORRECT ANSWERS Restore AV synchrony
in ventricular only PM -->lower the pacing rate to minimize ventricular only pacing
DO NOT increase the pacing rate
Fallback - CORRECT ANSWERS 1. Decouples atrial & ventricular events at the upper rate limit
2. The ventricular inhibited pacing rate then gradually decrements to a programmed lower or
"fallback" rate over a programmed duration
UPDATE 2024/2025 ALL ANSWERS 100% CORRECT
VERIFIED BEST EXAM SOLUTION GRADED A+ FOR
SUCCESS
Rheobase - CORRECT ANSWERS the lowest point on a strength duration curve at an infinitely long
pulse duration
Chronaxie time - CORRECT ANSWERS the pulse width at twice the rheobase value. It approximates
the most efficient stimulation pulse duration
Charge (formula) - CORRECT ANSWERS Charge= I(current) x T(time)
Furman's formula - CORRECT ANSWERS Energy(microjoules)= I(current)xV(voltage)xT(pulse width)
Ohms law formula - CORRECT ANSWERS Voltage(electromotive force)= I(current/flow of electrons) x
R(resistance to current flow in ohms)
Functional Refractory Period - CORRECT ANSWERS the coupling interval which first results in a
measurable degree of delay in impulse conduction
Effective Refractory Period - CORRECT ANSWERS the longest coupling interval to be associated with
block
Devices with NO interaction with pacers - CORRECT ANSWERS 1. microwave oven, 2. CT
scan/Ultrasound 3. X-rays (diagnostic)
Devices that cause transient or 1 beat inhibition - CORRECT ANSWERS 1. EAS 2. Cellphones 3. Arc
Welding 4. airport metal detector 5. TENS 6. Electric appliances such as electric blanket & power
tools
Devices that may damage the pacemaker - CORRECT ANSWERS 1. MRI 2. Defibrillator 3.
Cardioversion 4. Cautery/RF Ablation 5. Radiation Therapy
Resistance in Series - CORRECT ANSWERS Series means the beginning of one resistance is connected
to another
,CCDS IBHRE EXAM QUESTIONS AND ANSWERS LATEST
UPDATE 2024/2025 ALL ANSWERS 100% CORRECT
VERIFIED BEST EXAM SOLUTION GRADED A+ FOR
SUCCESS
Sum the resistances: R1+R2= total resistance. EX: A LEAD FRACTURE (fractures INCREASE impedance)
Resistance in Parallel - CORRECT ANSWERS Parallel means all the resistances are connected to the
same point.
(R1xR2)/(R1+R2)= total resistance
EX: LEAD INSULATION DEFECTS (insulation defects DECREASE impedance)
Permanent pacemakers are constant voltage or constant current? - CORRECT ANSWERS ALL
permanent pacemakers are constant voltage devices.
SOME temp pacemakers are constant voltage, most are constant current.
LOAD - CORRECT ANSWERS Load refers to impedance (or resistance) applied to a circuit.
A system with a SMALL load (low impedance) applied to the circuit is said to be a constant current
device
A system with LARGE load is said to be a constant voltage device
Guidelines for Permanent Pacing - CORRECT ANSWERS 1. Patient is symptomatic
2. The heart rate is less than 40 bpm
3. Asystole of greater than 3 seconds is documented
NOTE: Pt may be asymptomatic with 2 or 3
Slew Rate - CORRECT ANSWERS Slew rate = peak slope of an electrogram
,CCDS IBHRE EXAM QUESTIONS AND ANSWERS LATEST
UPDATE 2024/2025 ALL ANSWERS 100% CORRECT
VERIFIED BEST EXAM SOLUTION GRADED A+ FOR
SUCCESS
slew rate= change in voltage/ change in time
Normal slew rate in atrium - CORRECT ANSWERS >.3 V/s
Normal slew rate in ventricle - CORRECT ANSWERS >.5V/s
Steroid used in electrodes - CORRECT ANSWERS dexamethasone sodium phosphate in the silicone
core(a corticosteriod)
Steroid-Eluting Electrodes - CORRECT ANSWERS 1. The acute threshold is relatively flat compared to
non-steroid electrodes
2. The initial capture threshold is similar to non-steroid leads
Silicone Rubber lead insulation Pros - CORRECT ANSWERS 1. Can easily be repaired
2. Flexible
3. Proven performance history
4. Easy to make
Silicone Rubber lead insulation cons - CORRECT ANSWERS 1. high friction coefficient
2. Absorbs lipids
3. More thrombogenic and fibrotic
4. Cuts easily
5. Tears easily if suture tied too tightly
6. Large diameter
Polyurethane 80A - CORRECT ANSWERS BAD
Polyurethane 55D - CORRECT ANSWERS GOOD
, CCDS IBHRE EXAM QUESTIONS AND ANSWERS LATEST
UPDATE 2024/2025 ALL ANSWERS 100% CORRECT
VERIFIED BEST EXAM SOLUTION GRADED A+ FOR
SUCCESS
polyurethane lead insulation pros - CORRECT ANSWERS 1. relatively nonthrombogenic/fibrotic
2. thin walls
3. high tear friction
4. resists cutting
5. low friction coefficient
polyurethane lead insulation cons - CORRECT ANSWERS 1. cannot be repaired
2. relatively stiff
3. hard to make
Pacemaker Syndrome Causes - CORRECT ANSWERS 1. Loss of AV synchrony
2. Sustained retrograde conduction
3. A single ventricular rate when rate modulation is required for exercise
Approx 25% of patients only paced from the ventricle may have some level of severity related to
pacemaker syndrome
Pacemaker syndrome diagnosis - CORRECT ANSWERS 1. Observe fluctuation in the peripheral blood
pressure
2. Cannon "A" wave in the neck
3. History alone
Pacemaker syndrome management - CORRECT ANSWERS Restore AV synchrony
in ventricular only PM -->lower the pacing rate to minimize ventricular only pacing
DO NOT increase the pacing rate
Fallback - CORRECT ANSWERS 1. Decouples atrial & ventricular events at the upper rate limit
2. The ventricular inhibited pacing rate then gradually decrements to a programmed lower or
"fallback" rate over a programmed duration
