IBHRE Study set

An IS-1 bipolar lead is compatible with which of the following connector blocks?

VS-1A long cavity with no sealing rings, IS-1 unipolar connector block, VS-1B long cavity with sealing rings

What are the two most common causes of ventricular safety pacing ?

Ventricular ectopy and loss of atrial sensing

Which of the following uses the same MICS and might cause long range interference with CRM device remote monitoring ?

Weather balloons

This component protects the pacemaker circuitry from high external voltages such as external defibrillation?

Zener diode

What lead insulation materials are known for reducing fibroblast in growth and susceptibility to MIO and ESC?

ePTFE and 80A polyurethane

What does one French size equal?

0.3mm

iatrogenic CHB occurs in aproximately _________ % of patients undergoing ablation of the slow pathway for AV nodal reentry tachycardiaR?

1%

Defibrillation energies exceed pacing energies by a factor ?

1,000,000

AV block occurs in approximately what % of congenital open heart surgeries ?

1-3%

What would the energy be given a voltage of 2V a pw of 1ms and an impedance of 400ohms?

10 uj

1.67 Hz would equal how many bum?

100 bpm

Which of the following would most comply with recent guidelines for performing life support compressions?

2-2.4 inches at 100-120bpm

A 75 yo pt with a fib is being treated with warfarin to help prevent stroke. Which of the following INR values would be the most appropriate ?

2-3

At what point does the threshold begin to rise in tined leads ?

2-3days

In a circuit with resistance of 500ohms and 600ohms in parallel, the circuit resistance would be ?

273 ohms

A pt presents with pulse less arrest. Which of the following energies should be utilized for a monophasic AED when multiple shocks are required?

360-360-360J

What is the estimated battery service life of a pacemaker with a 1 amp hr battery and a 20 micro amp current drain ?

5.7 years

In a normal person, stroke volume increases by what % when exercising ?

50%

Which of the following pacing modalities has been shown to reduce p wave amplitudes and has also shown beneficial effects in patients with intraatrial conduction delays and atrial tachyarrhythmias ?

Bachmans bundle pacing

What electrode material would most likely result in higher pacing thresholds and high polarization?

Elgiloy

Match the unit: watt-second

Energy

A pt with long QT is scheduled for an ICD. Which of the following drugs should be avoided due to an increased risk for torsades de pointes?

Erhythromycin

It has been well described that a critically timed pulse delivered into a VT circuit and possibly within the first few seconds of a VF episode could trigger a wave front block that could terminate the tachycardia. This area of tissue out in front of the fibrillation wave front is known as the ?

Excitable gap

The basic unit of capacitance is called?

Farad

Which of the followings patients is at the highest risk for SCD with long QT?

Female, low serum potassium, class 1a

The term S2 refers to the ?

First premature stimulus

Which of the following drugs will increase DFT within 2 days?

Flecanide

Faster and longer range telemetry, new therapies and physiologic sensors in pacemakers requires higher peak power outside the range of Li/I2 batteries. Which of the following battery chemistires Is now incorporated into some pacemakers?

Lithium silver vanadium oxide and lithium carbon monofluoride

Which of the following risk factors would carry the highest risk for infection?

Long term immunosuppresive therapy

An elderly woman had been taking the following meds: lasix and maxide. Her son wanted to save money on his mothers meds so he had her double up on the lasix and stops the maxide. Ten days later his mother died. One possible cause of her death could be ?

Loss of potassium led to ventricular arrhythmias

T wave frequencies are typically ?

Low

A patient is having an ICD battery change and the physician notices an insulation problem on the sense/pace portion of the lead.he puts in a new lead and hooks it into the pace/sense portion of the ICD. During DFT testing there is a loud pop in the pocket. What can one expect to find ?

Low HV impedance

What test is typically performed during exercise with heart rates in the range of 105-110bpm and was shown to have a negative predictive value in the MADIT II and SCD-HeFT type patients ?

Microvolt t wave alternans

Which of the following drugs would have the least analgesic effect?

Midazolam

In order to have a pacing system automatically assess capture and stimulation thresholds, the essential electrode characteristics would be?

Minimal electrode after potential characteristics

Upper arm movement interference is a sensor driven idiosyncrasy linked to transthoracic impedance measurement in which of these ?

Minute ventilation

What is an example of a closed loop sensor ?

Myocardial contractility

During an implant the physician suspects that he has perforated the RV and the retracts and repositions the lead. Which of the following clinical sequela and test combinations would be the most common clinical outcome and desirable test for monitoring this patient with an acute RV perforation ?

No clinical sequela, echocardiogram

A surface electrode is placed over conducting tissues. What does the ECG look like when the depolarization is directly below/under the electrode ?

No waveform deflection

During ICD testing the introducer guide wire is inadvertently left in position in the RA. The result could be ?

Non conversion of VF

The ventricoloatrial conduction time of a pacemaker patient with a typical endless loop tachycardia may be calculated by what equation?

None

Extensive ecchymosis that is not expanding following device implantation should be treated by?

Observation

Which of the following is most responsible for the rapid repolarization phase 3 of the cardiac action potential ?

Outflow of K+

Each of the following limited sensitivity diagnostic tools has been shown to be a positive predictor for increased risk of sudden cardiac death except ?

P wave dispersion

What refers to the decline in leading edge voltage at the time of truncation?

Percent tilt of an ICD waveform

Which phase of the action potential would correlate to the relative refractory period?

Phase 3

The isovolumetric time from electrical depolarization of the heart to mechanical systole describes which of the following terms ?

Pre ejection interval

Which of the following steroids is not used in modern pacing leads ?

Prednisone

Fluoroquinolones , a new generation of broad spectrum oral antibiotics, is known for which of the following cardiac effects ?

Prolonging the QT

Inaccurate PVC counts with inappropriate PVARP extension may result from what?

R wave double counting, intrinsic p waves falling in PVARP, intermittent atrial under sensing

A pt has exercise induced VT with sinus rates that crossover into the VT detection zone. One would most likely choose the following criteria to optimize specificity for VT detection?

Rate and morphology discrimination or EGM width

What is the electrical circuit that converts a signal with both positive and negative components into a signal with only one component ?

Rectifier

Which of the following would decrease both the simulation threshold and the current drain?

Reduce electrode surface area from 12 to 8mm2

Which of the following was a secondary endpoint finding of the CTOPP and MOST studies comparing atrial and versus ventricular based pacing ?

Reduced onset of AF

What parameter would not be useful to prevent typical crosstalk?

Safety pacing

Which of the current ICD capacitor technologies provide the highest energy density and does not require reform?

Tantalum electrolytic

Immediately after implant, a patient experience chest pain and sob. There is no hypotension, pulse paradoxus, electrical alternans or double shadow of the cardiac silhouette. The patient is most likely experiencing which of the following?

Tension pneumothorax

What is the primary reason that the lithium iodine battery has not been used for ICDs?

The battery chemistry is only 2.8V

The wedensky effect may be greatest, reaching clinical significance with threshold testing at which of the following parameters?

Short pulse widths

Which of the following sensing related parameters represents the maximal rate of change of the electrical potential between the sensing electrode and is the first derivative of the egm?

Slew rate

What would shift the defibrillation dose response curve to the left ?

Sotalol or dofetilide

For treatment of arrhythmias, most drugs work by ?

Altering conductivity or refractoriness

Real time measured telemetry yields a bipolar impedance reading of 100ohms and a unipolar reading of 450 ohms, which of the following is most likely concerning the lead ?

Coaxial design

Normal ejection fractions are in which of th following ranges ?

50-65%

Which of the following values would most likely indicate nearing ERI in the lithium iodide pacemaker ?

5000 ohms

Which of the following pace/sense lead designs would one expect the highest current density with a bipolar impedance reading of 1100 ohms ?

A Brady lead with an anode 5mm2 and cathode 1.2mm2

The term virtuous electrode or fibrous capsule surrounding the electrode can mean ?

A normal foreign body reaction, an inexcitable capsule of tissue, decreases the current density at the lead tissue interface

A young boy has congenital CHB. What factor would be considered most important for him to receive a pacemaker ?

A wide qrs with mild ventricular dysfunction

Which of the following studies using an end point of total mortality looked at rate vs rhythm control and concluded rate control with anti coagulation was as effective ?

AFFIRM

What programming changes would cause the most significant hit on an ICD battery longevity ?

ATP during charge

The arithmetic difference etween the rate of events in the experimental and control groups is best described by the term ?

Absolute risk reduction

Which of the following factors may elevate myocardial stimulation thresholds?

Acidosis, alkalosis. Hypoxia

Which of the following would be the drug of choice in terminating an SVT of 200bpm in a 35 year old patient ?

Adenosine

What drug may reduce digoxin clearance by 30% resulting in the need to reduce digoxin dose and retitrate based on serum level determinations?

Amiodarone

Which of the following would be the drug of choice when treating CHF patients with symptomatic or serious arrhythmias?

Amiodarone 300mg

Which of the following conditions is most prone to abrupt CHB and would require emergency temporary pacing ?

An anterior MI with some non conducted p waves

Which of the following RV leads would be least prone to anodal stimulation in an extended bipolar configuration with a unipolar LV lead when BiV pacing ?

An integrated ICD lead with an anode 450mm2 and cathode 2mm2

What would account for the most common cause of inappropriate mode switching ?

Atrial lead sensing ventricular signals

An 8 year old boy collapses during a football game and is pulse less and not breathing. The coach initiates CPR and EMTS are called. An AED arrives but only has adult pads. What is best next course of action?

Attach the AED and shock for VT/VF

Which of the following pacemaker components is most susceptible to cumulative damage from high doses of radiation?

CMOS (the circuitry)

Which of the following is most likely to trigger the EOL in an ICD?

Capacitors charging

Which of the following is the most likely indication for a pacemaker in a pt following an orthotropic heart transplant ?

Chronotropic incompetence

A 65yo pt experiences syncope and wrecks his car while turning his head to make a sharp right turn. Further follow up yields a 3.1 second pause during carotid sinus massage in the absence of cardioinhibatory medications. This hx would fall under which can of the following pacing indications ?

Class 1

First or second degree AV block with symptoms suggestive of pacemaker syndrom is which of the following indications ?

Class IIa

Battery capacity of a pacemaker is given in which of the following parameters ?

Current

What conductor technology combines a silver core with a high strength metal (MP35N0) to obtain a strong low resistance wire?

DFT

Which of the following tests is performed over 10-20 beats following a PVC and whose absence is a predictor of cardiac mortality following an MI?

Heart rate turbulence

This test has been used as a tool for assessing autonomic modulation of the sinus node. This parameter decreases in heart failure patients as a result of down regulation of beta receptors?

Heart rate variability

A band pass filter modifies incoming signals according to which of the following units of measure ?

Hertz

Which of the following conditions has been shown to cause an increase in stimulation threshold, a wide qrs, latency or under sensing ?

Hyperkalemiad

Which of the following EMI sources has recently been implicated in causing over sensing and telemetry interference in pacemakers ?

IPODS/MP3 players/headphones

During the late stages of expertise test on a treadmill, a symptomatic pt demonstrates both mobitz 1 and intermittent mobitz 2 blocks. What should be done next for this pt?

Implant a pacemaker

What would deplete a pacemaker battery most quickly ?

Increase average current drain

Which of the following clinical trial terms best describes patients analyzed in the group they were randomized to regardless of whether they received or adhered to the intervention ?

Intention to treat analysis

The horizontal asymptote of a strength duration curve defines which of the following?

Rheobase

What part of the Doctor is considered part of the sterile field?

Right shoulder

What is the strength above which VF is no longer inducible?

The upper limit of vulnerability

A 28 yo presents with orthostatic hypotension and 3 episodes of sudden syncope I the last 3 months. A routine physical exam, blood work and ECG reveal no abnormalities. What test might be recommended to determine the cause of syncope ?

Tilt table test

What battery discharge curve shape does a lithium silver vanadium oxide battery make ?

Two humps

If one has the physiologic substrate for reentry which of the following would be necessary to intiate the reentry tachycardia ?

Unidirectional block of one pathway