CCDS IBHRE Questions with 100- Correct Answers

CCDS IBHRE Questions with 100%
Correct Answers

Rheobase |Correct |Answer: |the |lowest |point |on |a |strength |duration |curve |at |an
| infinitely |long |pulse |duration


Chronaxie |time |Correct |Answer: |the |pulse |width |at |twice |the |rheobase |value. |It
| approximates |the |most |efficient |stimulation |pulse |duration


Charge |(formula) |Correct |Answer: |Charge= |I(current) |x |T(time)


Furman's |formula |Correct |Answer: |Energy(microjoules)=
| I(current)xV(voltage)xT(pulse |width)


Ohms |law |formula |Correct |Answer: |Voltage(electromotive |force)= |I(current/flow
of |electrons) |x |R(resistance |to |current |flow |in |ohms)
|




Functional |Refractory |Period |Correct |Answer: |the |coupling |interval |which |first
results |in |a |measurable |degree |of |delay |in |impulse |conduction
|




Effective |Refractory |Period |Correct |Answer: |the |longest |coupling |interval |to |be
| associated |with |block


Devices |with |NO |interaction |with |pacers |Correct |Answer: |1. |microwave |oven, |2.
| CT |scan/Ultrasound |3. |X-rays |(diagnostic)


Devices |that|cause |transient|or |1 |beat|inhibition |Correct |Answer: |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 |Answer: |1. |MRI |2.
| Defibrillator |3. |Cardioversion |4. |Cautery/RF |Ablation |5. |Radiation |Therapy

,Resistance |in |Series |Correct |Answer: |Series |means |the |beginning |of |one |resistance
| is |connected |to |another




Sum |the |resistances: |R1+R2= |total |resistance. |EX: |A |LEAD |FRACTURE |(fractures
INCREASE |impedance)
|




Resistance |in |Parallel |Correct |Answer: |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
| Answer: |ALL |permanent |pacemakers |are |constant |voltage |devices.




SOME |temp |pacemakers |are |constant |voltage, |most |are |constant |current.


LOAD |Correct |Answer: |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 |Answer: |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 |Answer: |Slew |rate |= |peak |slope |of |an |electrogram




slew |rate= |change |in |voltage/ |change |in |time


Normal |slew |rate |in |atrium |Correct | Answer: | >.3 |V/s


Normal |slew |rate |in |ventricle |Correct |Answer: |>.5V/s


Steroid |used |in |electrodes |Correct |Answer: |dexamethasone |sodium |phosphate
in |the |silicone |core(a |corticosteriod)
|




Steroid-Eluting |Electrodes |Correct |Answer: |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 |Answer: |1. |Can |easily |be |repaired

, 2. Flexible


3. Proven |performance |history


4. Easy |to |make


Silicone |Rubber |lead |insulation |cons |Correct |Answer: |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 |Answer: |BAD


Polyurethane |55D |Correct | Answer: |GOOD


polyurethane |lead |insulation |pros |Correct |Answer: |1. |relatively
nonthrombogenic/fibrotic
|




2. thin |walls


3. high |tear |friction


4. resists |cutting


5. low |friction |coefficient


polyurethane |lead |insulation |cons |Correct |Answer: |1. |cannot |be |repaired