Q201-227

Important features that are needed for Pediatric patients

- High output capabilities: MANDATORY especially with epicardial system. *Many children have significant initial threshold rise. - Wide range of lower & upper rate limits: Low = 50-120bpm MTR = 180-220bpm - Rate adaptive PVARPs -- to allow high MTRs (esp. in HB pts.) *V-A conduction in children = RARE -Rate adaptive AV delays -- to allow high MTRs (esp. in HB pts.) -Rate responsive pacing -- helpful if sinus node is unreliable *** Deceleration programmed to be at least 10 minutes!***

Regarding Figure 209, the EKG's were taken from an Autocapture algorithm. What is the stimulation threshold and signal to noise (polarization) ratio respectively?

A: 1.75V and 22.0 : 0.39

Which of the following features may explain why a pacemaker-mediated tachycardia may only be initiated when atrial rates are faster than 100 ppm?

A: Adaptive PVARP

Regarding Figure 212, both EGMs below represent post shock pacing from two consecutive episodes. What device parameter was reprogrammed in EGM #2 to address the problem seen in EGM #1?

A: Atrial Output

A 78-year-old female was implanted with a DDDR pacemaker for symptomatic sinus bradycardia with left bundle branch block. Routine follow-up in the clinic yielded the following ECGs and programmed telemetry.

A: Atrial Sensing

Regarding Figure 221, the atrial pace in the bottom strip occurs as a result of:

A: Atrial Undersensing

Which of the following is the most common reason for a pacemaker classifying a false VT/VF episode?

A: Atrial Undersensing

Regarding Figure 208, why are the circled P-waves not being tracked?

A: Atrial refractory - PVC Response -PVC Response: extends PVARP to 400ms Two reasons for PVC Response: 1. DDDR, DDD. and VDD (tracking) - PVC response is intended to prevent tracking of retrograde P-waves. This response helps prevent initiation of PMT. 2. DDIR and DDI (nontracking) - PVC response prevents inhibition of atrial pacing that can result from retrograde P-waves generated by PVCs. ** PVC to device is ANY VS Event (refractory or nonrefractory) that follows a Ventricular event (pace, refractory sense, or nonrefractory sense) without an intervening Atrial event. -- VS or VR following a Ventricular event (VP, VR, or VS)

A DDD patient presents with VVI pacing at 65 bpm. Which of the following would be the best way to determine if the device is at ERI or in Power-on- Reset mode?

A: Battery Voltage reading

Regarding Figure 214, assuming that the pacemaker is programmed appropriately, what is the patient's most likely indication for pacing?

A: Complete Heart Block

Regarding Figure 221, the ability to mode switch in the presence of fine atrial fibrillation may be enhanced by each of the following except:

A: Decrease PVARP Other Options it was NOT: -Increase Atrial Sensitivity -Decrease Mode Switch rate -Decrease PVAB

Regarding Figure 203, what should the physician do with the situation featured in the ECG strips if the pacemaker did not immediately respond to programming? In this example, ventricular capture was able to be lost in the bottom strip.

A: Detach the leads

Which of the following EMI sources would most likely put a pacemaker into a power on reset or back-up mode?

A: Electrocautery Other options: -Myopotential noise -Cellphone -Electronic article surveillance gate

Regarding Figure 218, which of the following does a pacemaker utilize to prevent ventricular pacing above the upper tracking rate during a PMT?

A: Extend the AV Clock

Regarding Figure 224, in the ECG's below; which of the following would one program to make ECG A look like ECG B not knowing if the patient may be pacemaker dependent?

A: Increase AV Delay

Regarding Figure 207, if one wanted to prevent mode switching from taking place in the EGM's, which of the following options would be most effective?

A: Increase PVAB or decrease atrial sensitivity

Regarding Figure 226, during a routine pacemaker follow up visit, the above strip documents the parameters that were reprogrammed at this visit. Based on this information, what pacing change would you expect now in this patient?

A: Increased atrial pacing, less ventricular pacing, more sensor driven pacing "V-Low" Value programmed for Activity Threshold = MORE Rate response "Low" Value programmed for Activity Threshold = LESS Rate response than V-Low

Regarding Figure 227, the problem demonstrated by the 5 year old, steroid, polyurethane, bipolar system is most likely a result of:

A: Insulation Break

Which of the following would be most accurate when contrasting the subclavian approach to the cephalic approach of transvenous lead introduction?

A: Lung laceration- high, crush - high, aterial puncture -high

Regarding Figure 221, what accounts for the differences in ventricular rates between the top and bottom ECG in the figure above?

A: Mode Switching

Regarding Figure 225, which of the complexes labeled below most likely demonstrates a fusion beat?

A: Morphology C

Which group of programmable features would be most likely to promote episodes of repetitive nonreentrant ventriculoatrial synchrony (RNRVAS) also called AV desynchronization arrhythmia?

A: Rate responsive pacing & long PVARPs anything that promotes atrial pacing -- so when we rate responsive pace in dual chamber device that is rate responsive pacing Long PVARP - would set the stage for an atrial event to fall into it and be ignored causing atrial pacing to follow that (AS) = an AS that falls into pvarp

Regarding Figure 205, the ECG's were obtained from a 56-year-old female who underwent high dose radiation therapy without taking device precautions. The DDD pacemaker was programmed to 60 bpm AV 150ms & MTR 125 bpm. What should be done?

A: Replace the device

Which of the following is likely to fail first when a pacemaker reaches EOL?

A: Telemetry and Programming capabilities

Regarding Figure 204, the intracardiac electrograms featured shows the RV on the VEGM and the LV on the AEGM. This measurement is useful to determine?

A: The amount of separation between the two BIV electrodes

Regarding Figure 215, which of the following most likely explains the ventricular rate below?

A: Ventricular Based Timing

Regarding Figure 210, the non-sensed R-wave in the fifth complex of ECG strip #1 could be explained as normal function due to:

A: Ventricular Blanking

Which of the following programming availabilities would be most desirable when implanting an epicardial pacemaker in an 18 month old with congenital heart block?

A: base rate 110, dynamic PVARP & AV, high output

Repetitive Nonreentrant Ventriculoatrial Synchrony (RNRVAS)

Requires: 1. VA conduction 2. P-waves in PVARP (functional non-sensing) 3. A-Pacing in tissue refractory (functional non-capture) Promoted by: -High low rates AV sequential pacing rates -DDDR (rate responsive pacing) -features that allow rapid AV pacing, ie. rate drop response, SBR, atrial overdrive pacing algorithms -Long AV delays -Long PVARP's