Device & feature selection

Question 1

What percentage of SND patients also present with AV conduction disturbances?

Answer 1

20%

Thus consider DDD vs. AAI device.

Question 2

What is the 5yr risk of progression to AV block for patients presenting with SND?

Answer 2

5-35%

Thus consider DDD vs. AAI device.

Question 3

Yes / No

When selecting a pacing mode for SND - is DDD considered better than VVI.

Answer 3

Yes.

DDD is better than VVI as it maintains AV synchrony - Class I indication.

Question 4

True

Programming to minimise RV pacing is beneficial for reducing risk of AF onset.

Answer 4

True.

Reduced RV pacing is associated with reduced AF incidence - Class IIa indication.

Question 5

True / False

AAI may be considered in patients with SND with normal AV conduction.

Answer 5

True.

This is a class IIb indication, thus the research is debateable.

Question 6

What is the likely device implanted and mode programmed for the following patient?

Patient has permanent AF and AV conduction disease.

Answer 6

Single chamber device - Programmed VVI/VVIR.

Question 7

Patients who present with AV block should recieve a DR PPM over a SR PPM unless its clinically impossible to pass multiple leads.

Answer 7

True

This is a Class I indication

Question 8

True / False

A DR device should be implanted in patients with permanent AF.

Answer 8

False.

This is a Class III indication. Only a SR device should be considered.

Question 9

Overdrive ventricular pacing at rates >100bpm is preventative for what arrhythmia?

Answer 9

Torsades (TdP).

Question 10

List 5 reasons why His Bundle pacing systems are inferior to conventional pacing systems?

Answer 10

1. Longer implant time
2. Higher risk of lead dislodgement
3. Steep learning curve - Operator skill
4. High Thresholds
5. Not applicable to patients with BBB

Question 11

Yes / No

Can AAI mode be considered in patients with AVB?

Answer 11

No.

AAI will pace the Atria - however conduction will not continue to the ventricles due to the AVB, which will result in ventricular standstill if no intrinsic escape is present.

Question 12

When selecting a pacing mode for SND - is AAI better than VVI?

Answer 12

Yes.

AAI is considered better than VVI due to maintenance of AV synchrony - This is a Class I indication.

Question 13

Yes / No

When selecting a device for SND - is a DR device better than an SR device?

Answer 13

Yes - DR > SR (Atrial).

This is due to the risk of developing AVB further down the track and having to revise to a DR system if an SR system is chosen. This is a Class I indication.

Question 14

Yes / No

Would you program an RV reduction algorithm in an AVB patient?

Answer 14

No.

Depending on algorhythm this will result in extended AV delays or pauses to which the patient will be symptomatic. Both will cause significant AV dyssynchrony and potentially pacemaker syndrome.

Question 15

Yes / No

Would you program negative hysteresis in a patient with intrinsic conduction?

Answer 15

No.

Negative hysteresis denies intrinsic conduction by shortening the AVD when an R-wave is sensed, thus ensuring as close to 100% pacing as possible. Useful in CRT, however if a patient has intrinsic conduction this is not only unnecessary but hightens risk of pacing-induced cardiomyopathy.

Question 16

Yes / No

Would you program positive hysteresis in a patient with CRT?

Answer 16

No.

Positive hysteresis promotes intrinsic conduction via lengthening of the AVD. The target for CRT is to achieve as close to 100% CRT-pacing as possible. Suppression of intrinsic conduction is achieved via negative hysteresis.

Question 17

True / False

For carotid sinus hypersensitivity, DDDR pacing with a rate-drop/sudden brady response feature is advisable.

Answer 17

True.

Question 18

True / False

Sinus node dysfunction (SND) and atrioventricular (AV) block are the primary indications for pacing.

Answer 18

True.

Question 19

True / False

AAI/AAIR pacing is indicated for the following.

‘Patients who have isolated SND and no known / anticipated AV block’.

Answer 19

True.

Question 20

True / False

AAI/AAIR pacing in patients with SND results in a lower indicence of AF, CHF and mortality vs. VVI/VVIR pacing.

Answer 20

True.

Question 21

True / False

AAI/AAIR pacing can be considered a cost-effective alternative in patients with isolated sinus node dysfunction.

Answer 21

True.

The incidence of clinically significant AV node disease being less than 2% per year.

Question 22

True / False

VVI/VVIR pacing is indicated for patients with chronic atrial arrhythmias that are expected to return to sinus rhythm.

Answer 22

False.

VVI/VVIR devices would be applicable if the arrhythmia was permanent and sinus rhythm was not expected to return.

Question 23

True / False

VVI/VVIR protects patients from lethal bradyarrhythmias, while maintaining AV synchrony.

Answer 23

False.

This lack of AV synchrony may lead to pacemaker syndrome.

Question 24

AAI or DDD pacing maintains AV synchrony. This substantially reduces stroke, atrial fibrillation, heart failure and mortality indicators when compared to VVI pacing.

Answer 24

True.

Question 25

The following are 3 risk factors for the development of LV dysfunction respondent to VVI pacing. 1. Elderly (age over 70 years) 2. Pre-existing or new CAD 3. Pre-existing BBB or wide QRS complexes

Answer 25

True. ## Footnote *Note that only a small percentage of patients with VVI/VVIR pacing develop LV dysfunction.*

Question 26

# True / False Only a small percentage of patients with VVI/VVIR pacing develop LV dysfunction.

Answer 26

True.

Question 27

VDD and DDD systems comprise the two forms of dual-chamber pacing systems used today.

Answer 27

True.

Question 28

# True / False VDD pacing system is indicated in patients with SND, AV block and near-normal heart structure.

Answer 28

False. ## Footnote *Due to a lack of atrial pacing, VDD is contraindicated in patients with SND. VDD would be suitable if they had normal sinus node function.*

Question 29

List 3 benefits of VDD systems vs conventional DDD systems.

Answer 29

1. Significantly shorter implantation time 2. Fewer early and long-term complications 3. Significantly lower overall costs

Question 30

Atrial sensing is rarely optimal with a single pass VDD lead.

Answer 30

True. ## Footnote *This is due to the atrial electrode 'floating' in the atria and not being attached to myocardium as with conventional leads.*

Question 31

# True / False DDD pacing is associated with a higher rate of complications vs. AAI/VVI devices.

Answer 31

True.

Question 32

# True / False The derived benefit of AV synchrony provided by DDD systems may be attenuated if the RV lead is placed in the apical position - why?

Answer 32

True - RV Apical pacing contributes to ventricular dyssynchrony. ## Footnote *To avoid this other RV positions such as septal or HIS may be selected.*

Question 33

Optimisation of the mode-switch feature is important to prevent tracking of atrial arrhythmias.

Answer 33

True. ## Footnote *Optimisation should facilitate quick entry into AMS setting and more difficult criteria to exit AMS. This is due to the likelihood of atrial undersensing during AF which could fool a system into exiting AMS without true arrhythmia termination.*

Question 34

# True / False Shocks are preferred to ATP for initial therapy of haemodynamically tolerated ventricular tachycardia.

Answer 34

False. ## Footnote *ATP is preferred due to greater than 90% success rate while being pain free.*

Question 35

Scrutiny exists with respect to prophylactic ICD implantation post MI as per MADIT-II guideline.

Answer 35

True. ## Footnote *A significant proportion of these patients never receive therapy during their lifetime. Calling for improved patient selection criteria.*

Question 36

Approximately 10% of ICD patients who recieved prophylactic ICD implantation post MI as per MADIT-II guideline experience inappropriate shocks.

Answer 36

True.

Question 37

Which of the 4 states of DDD pacing is most likely? Patient has good sinus node function and good AV node function.

Answer 37

AsVs.

Question 38

Which of the 4 states of DDD pacing is most likely? Patient has a good sinus node function but poor AV node conduction.

Answer 38

AsVp.

Question 39

Which of the 4 states of DDD pacing is most likely? Patient has poor sinus node function but has intact AV node conduction.

Answer 39

ApVs.

Question 40

Which of the 4 states of DDD pacing is most likely? Patient has a poor function in both the sinus node and AV node.

Answer 40

ApVp.

Question 41

Deduce the mode. 1. Unable to pace the atrium 2. Intrinsic atrial activity can trigger an AV delay resulting in P-wave tracking 3. Maintains AV synchrony

Answer 41

VDD.

Question 42

Deduce the mode. 'Sinus node rates below the pacemaker programmed lower rate will cause AV dissociation'

Answer 42

VDD - As there is an inability to pace in the atrium. ## Footnote *AAI or DDD system would deliver an atrial stimulus and maintain AV synchrony. VVI systems cannot maintain AV synchrony.*

Question 43

# True / False VDD mode should only be used in patients with good SA node function.

Answer 43

True.

Question 44

Deduce the mode. 'Patient has extremely high atrial capture threshold. Programming this mode will circumvent the issue by maintaining atrial sensing and thus AV synchrony, while also conserving battery life by not pacing. However patient must have acceptable sinus node function'.

Answer 44

VDD.

Question 45

Deduce the mode. 'Primary use is in patients with atrial tachyarrhythmias and mode switch algorithms'.

Answer 45

DDI.

Question 46

Which mode is appropriate in this case? 'P wave tracking is excellent for AV synchrony; however, if the patient goes into AF it is unwise to track the atrium and resultantly pace the ventricle at a high rate'

Answer 46

DDI. ## Footnote *DDI mode will result in AV dissociation if the atrial rate increases above the mode switch rate (normally ~160bpm).*

Question 47

Deduce the mode. 'AV sequential pacing at the lower rate limit regardless of the heart's own intrinsic activity'.

Answer 47

DOO.

Question 48

Deduce the mode. 'Used only in specific situations, such as magnet application or when a patient is having surgery'.

Answer 48

DOO.

Question 49

# True / False Rate Response or Rate Adaptive Pacing is used in patients with chronotropic incompetence.

Answer 49

True. ## Footnote *Rate adaptive pacing will use either open or closed loop sensors to determine appropriate HR at any given time.*

Question 50

Which device and mode is most appropriate? 'Patient has chronic AF with chronotropic incompetence'.

Answer 50

Single chamber - VVIR.

Question 51

Which device and mode is most appropriate? 'Patient has chronic AF but is chronotropically competent'.

Answer 51

Single chamber - VVI.

Question 52

Which device and mode is most appropriate? 'Patient has paroxysmal AF with chronotropic incompetence'.

Answer 52

Dual chamber - DDDR.

Question 53

Which device and mode is most appropriate? 'Patient has paroxysmal AF but is chronotropically competent'.

Answer 53

Dual chamber - DDD.

Question 54

Which device and mode is most appropriate? 'Patient has sinus rhythm and AV conduction but is chronotropically incompetent'.

Answer 54

Either single chamber (AAIR) or dual chamber (DDDR). ## Footnote *Conventional thinking dictates a DDD system as superior due to the risk of SND patients developing AV block.*

Question 55

Which device and mode is most appropriate? 'Patient has sinus rhythm, AV conduction and is chronotropically competent'.

Answer 55

Either single chamber (AAI) or dual chamber (DDD).

Question 56

Which device and mode is most appropriate? 'Patient has sinus rhythm, no AV conduction and is chronotropically incompetent'.

Answer 56

Dual chamber - DDDR.

Question 57

Which device and mode is most appropriate? 'Patient has sinus rhythm, no AV conduction but is chronotropically competent'.

Answer 57

Dual chamber - DDD.

Question 58

What would be the most appropriate mode for this patient? 1. AAI 2. VDD 3. VVI 4. DDI

Answer 58

2 - VDD. ## Footnote *VDD (or also DDD) would provide atrial tracking and respondent Vp, thus maintaining AV synchrony. All other modes are insufficient for a CHB patient.*

Question 59

AF with RVR patient has AVN ablation + VVI PPM implanted. Why is the base rate set to 80bpm? 1. Decrease Mitral Regurgitation 2. Decrease Tricuspid Regurgitation 3. Improve Cardiac Output 4. Reduce RV remodelling 5. Reduce risk of VT

Answer 59

5 - Reduce risk of VT. ## Footnote *AF with RVR patients are at risk of SCD in the months post AVN ablation. It appears to be due to bradycardia induced VT - thus programming a higher base rate mitigates this risk somewhat.*

Question 60

Atrial pacing has been shown to reduce incidence of AF vs. Ventricular pacing. Why?

Answer 60

From the suppression of atrial premature beats which may trigger AF. ## Footnote *V-based pacing doesn't suppress atrial premature beats. On the contrary if the patient has VA conduction it may introduce more.*

Question 61

Which of the following are least likely to benefit from CRT. 1. 80yr old male, EF 55%, LBBB QRS 130ms, NYHA III 2. 45yr old female, EF 40%, LBBB, QRS 140ms, NYHA IV 3. 70yr old female, EF 55%, LBBB, QRS 130ms, NYHA II 4. 60yr old male, EF 50%, LBBB, QRS 130ms, NYHA III

Answer 61

3 - 70yr old female, EF 55%, LBBB, QRS 130ms, NYHA II ## Footnote *CRT devices are generally reserved for those with NHYA III or above. (MIRACLE, COMPANION, CARE-HF).*

Question 62

Which of the following is not a benefit of DDD pacemakers? 1. AV synchrony 2. Lower rate limit is achieved 3. Physiologic increases in HR 4. Two leads are required

Answer 62

4 - Two leads are required. ## Footnote *This is a disadvantage as extra hardware increases risk of failures. VDD leads somewhat negate this risk by using one lead only.*