IBHRE EXAM QUESTIONS WITH COMPLETE SOLUTIONS

IBHRE EXAM QUESTIONS WITH
COMPLETE SOLUTIONS
ICD Battery Types - ANSWER1. Li/SVO: Lithium/Silver-Vanadium Oxide (1st gen.)
2. Lithium/Manganese Dioxide (2 manufacturers)
3. Lithium/Silver-Vanadium Oxide-Carbon Monofluoride (2 manufacturers -MDT)

Capacitor Types - ANSWER-Aluminum Electrolytic
-Tantalum

5 Phases of Cardiac Action Potential - ANSWER*Phase 0: influx of Na+ (depolarization
- conduction velocity)
*Phase 1: transient efflux of K+ (how quickly the cell can be depolarized again)
*Phase 2: influx of Ca 2+ & Na+ (")
*Phase 3: efflux of K+ > influx of Ca2+ & Na+ (")
*Phase 4: Na+ -K+ pump (resting phase, ion leakage determines when next
spontaneous depolarization will happen)

Excitable Periods of Cardiac Action Potential - ANSWERPhase 0, Phase 1, Phase 2

Refractory Periods of Cardiac Action Potential - ANSWERPhase 3 & Phase 4

Drugs That Increase DFTs - ANSWERLidocaine, Mexiletine, Flecainide, Quinidine,
Disopyramide, Moricizine, Propranolol, Verapamil, Amiodarone, Sildenafil Citrate

Drugs That Decrease DFTs - ANSWERSotalol, Dofetilide, Ibutilide

Drugs With Conflicting Data on DFTs - ANSWERProcainamide, Propafenone, Bretylium

Drugs That Increase Pacing Thresholds - ANSWERFlecainide, Propafenone, Encainide,
Sotalol, Beta Blockers, Lidocaine, Verapamil, Procainamide

Drugs That Decrease Thresholds - ANSWERAtropine, Catecholamines, Glucocoticoids

Drugs That Have No Proven Effect on Thresholds - ANSWERAmiodarone, Anesthetic
Drugs

Name of Class 1 Antiarrhythmic Drugs - ANSWER* 1a: disopyramide, procainamide,
quinidine
*1b: lidocaine, mexiletine
*1c: flecainide, propafenone

Class 1 Antiarrhythmic Drugs - ANSWERSodium Channel Blockers

, Name of Class II Antiarrhythmic Drugs - ANSWERmetoprolol, atenolol

Class II Antiarrhythmic Drugs - ANSWERBeta-blockers

Name of Class III Antiarrhythmic Drugs - ANSWERamiodarone, sotalol, ibutilide,
dofetilide, dronedarone

Class II Antiarrhythmic Drugs - ANSWERPotassium Channel Blockers

Name of Class IV Antiarrhythmic Drugs - ANSWERverapamil, diltiazem

Drugs Affect on Each Phase of Action Potential - ANSWER*Phase 0: Class I - Na+
Channel Blocker
*Phase 2: Class IV - Ca+ Channel Blocker
*Phase 3: Class III - K+ Channel Blocker
*Phase 4: Class II - Beta Blocker

Shocking Vectors (MDT vs. Others) - ANSWERB>AX = - > ++
AX> B = -- > +
B>A = - > +
A>B = -> +

Laser Lead Extraction - ANSWER1. Locking stylet introduced down lead lumen &
advanced to tip
2. Traction force directed to tip of lead and to aid in support
3. External outer sheath with beveled edge can be used over laser catheter for more
direct passage of adhesion into laser

Limitations to Laser Lead Extraction - ANSWER- Fractured lead may prevent stylet
passage
- Stylet dislocation with high force
- Adherent calcification cannot vaporize
- Insulation damage or externalized conductors can hinder tracking the laser over
catheter over
- Risk of myocardial injury/perforation

Mechanical Lead Extraction - ANSWER- Mechanical dilator sheath over the lead
- Uses rotational and reciprocating motion of internal cutting tool to chew fibrous
adhesion
- Lead pulled thru distal end of sheath w/manual traction

Limitations for Mechanical Lead Extraction - ANSWER- Works better for fewer
adhesions
- Most of the fibrous tissue still insitu and can obstruct further advancement of sheath
- Calcifications