CCDS IBHRE LATEST UPDATE 2024-2025 250
QUESTIONS AND VERIFIED CORRECT
ANSWERS GUARANTEED A+
1 hertz equals to how many bpm? - CORRECT ANSWER: 1 Hz = 60 bpm
- inverse square law to calculate exposure in relation to distance - CORRECT
ANSWER: I1/I2 = d2/d1
4 states of DDD pacing - CORRECT ANSWER: AV, PV, AR, PR
a successful ablation of slow pathway in AVNRT is indicated by: - CORRECT
ANSWER: 1. an accelerated junctional rhythm with 1:1 VA conduction during the burn
- an increase in refractoriness of the anterograde AV node
- elimination or alteration in dual AV nodal physiology
AAD eliminates through the vascular endothelium, erythrocytes - CORRECT ANSWER:
adenosine
Action potential - CORRECT ANSWER: 5 phases, the cellular characteristics of
depolarization and repolarization
Action potential phase 0 - CORRECT ANSWER: The depolarization phase
The rapid sodium channels are stimulated to open causing the resting transmembrane from above -90mV to about 0mV
Action potential phase 1 - CORRECT ANSWER: early repolarization
Action potential phase 2 - CORRECT ANSWER: The plateau phase
mediated by the slow calcium channels essentially disrupts and delays the repolarization started in phase 1 and prolonged the refractory period
Action potential phase 3 - CORRECT ANSWER: the end of repolarization
Action potential phase 4 - CORRECT ANSWER: the resting phase
ions leak back and forth between the membranes and cause a gradual increase in the transmembrane potential when the potential reaches the threshold voltage, the cell depolarizes.This spontaneous depolarization is called automaticity
adaptive burst - CORRECT ANSWER: starts as a percentage of the tachycardia cycle length
adding a subcutaneous patch to the defibrillation pathway would be expected to... -
CORRECT ANSWER: lower the output impedance 1 / 3
the tilt would be expected to increase
adding flecainide in a chronic stable pacing system may... - CORRECT ANSWER:
increase capture threshold
also other IC ADD or any type III agents including amiodarone or sotalol
Advantages and disadvantages of ATP - CORRECT ANSWER: advantage:
- minimal symptoms, immediate delivery of therapy
disadvantage:
- may need multiple burst, may accelerate the arrhythmia, prolonged high voltage
therapy
advantages of lithium/iodine cells battery - CORRECT ANSWER: 1. the self discharge rate is very low, which gives the pacemaker a long shelf life
- the voltage characteristics remain stable, allowing a clear delineation between
working voltage, recommended replacement time, and end of service
afterload - CORRECT ANSWER: the tension produced by a chamber of the heart in
order to contract pressure that heart has to generate in order to eject blood out of the chamber
Antitachycardia pacing - CORRECT ANSWER: a sequence of pacing impulses faster
than the tachycardia rate in an attempt to terminate an arrhythmia
- placing the pacing lead close to reentry site may increase ATP effectiveness
AR interval - CORRECT ANSWER: begins when the atrial escape interval (AEI) is
allowed to "time out" completely.An atrial output occurs at the end of the AEI, the AV delay interval is started but is interrupted by a sensed ventricular channel event(usually an intrinsic R wave)
Ashman's disease - CORRECT ANSWER: occasional wide complex beats during atrial
fibrillation with a right bundle branch morphology are due to aberrant conduction
at what point does the threshold rise in tined leads? - CORRECT ANSWER: 2-3 days
atrial escape interval - CORRECT ANSWER: the interval between a ventricular paced or sensed event and the subsequent atrial output pulse
atrial septal defect - CORRECT ANSWER: atrioventricular canal defect = endocardial cushion defect = atrioventricular septal defect one large valve allowing flow into the heart (instead of mitral and tricuspid) commonly seen in children with down syndrome
autodecremental pacing - CORRECT ANSWER: one needs to see multiple pacing
episode, each of which is occurring at a progressively faster rate 2 / 3
automatic interval - CORRECT ANSWER: the interval between two consecutive pacing stimuli occurring in the same chamber without an intervening sensed event in that same chamber
Automatic Mode Switching (AMS) - CORRECT ANSWER: When an atrial rate exceeds
a predetermined value, the device switches from a tracking DDD mode to a nontracking VVI mode At rates between the upper tracking rate and the mode switch rate, the device will exhibit pacemaker Wenkebach behavior until it reaches the 2:1 block point, it will then
begin 2:1 behavior
automaticity of the sinoatrial node is influenced by... - CORRECT ANSWER: the
autonomtic nervous system circulating catecholamines central venous temperature atrial stretch
AV delay interval - CORRECT ANSWER: the period of time between the atrial output pulse and the ventricular output pulse maybe fixed or variable atrial channel is refractory
AVID trial - CORRECT ANSWER: largest trial but shortest, using antiarhythmics vs ICD , most patients in AAD group receives amiodarone
patients with LVEF =35% survival was comparable, but for those with LVEF <35% survival from all cause and arrhythmic death was superior in patients who received ICD therapy
AVNRT - CORRECT ANSWER: - AV node can be thought of as divided into two
conduction pathways
- premature impulse is blocked in the fast pathway
- impulse travels down the slow pathway
- impulse again reaches the fast pathway in retrograde fashion
- impulse then reenter the slow pathyway
battery capacity in Ah(Ampere Hours), total or usable capacity - CORRECT ANSWER: Total battery = capacity includes the unusable capacity and overestimates the usefulness of the cell by about 10 percent Usable capacity = takes into account the lithium cells are only usable for about 85 to 90% of their total capacity
Bipolar coaxial lead failure due to which type of insulation? - CORRECT ANSWER:
Pellethane 80A insulation failure - Pacesetter 1016T and 1026T leads compression by retention sutures over a thin anchoring sleeve
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