MVP

Question 1

What does MVP stand for?

Answer 1

Managed Ventricular Pacing

Question 2

How does MVP work?

Answer 2

• looks for loss of ventricular conduction
• an A-A interval with NO V-sense will result in a ventricular pace 80ms after the next scheduled AP
• allows for V-V cycle variations and occasional pauses up to 2x the LR plus 80ms

Question 3

What should be done for a patient with sinus bradycardia or frequent loss of conduction to prevent long pauses in the V-V interval when programmed to MVP mode?

Answer 3

program the lower rate to 50bpm or higher prevents long V-V interval pauses

Question 4

What is required for the mode to remain in AAI(R) mode while programmed to MVP?

Answer 4

• need a VS event within every A-A interval
• time of VS or the length of the AV delay does not matter so long as a VS comes inbetween A-A intervals

Question 5

When is MVP programming not appropriate?

Answer 5

• for patients with symptomatic 1st degree AV block
• complete heart block
• symptomatic rate-dependent AV block
• suspected pause-dependent VT with no ICD backup

Question 6

When will MVP provide a backup VP?

Answer 6

• 80ms after the next schedule AP or A-A escape interval

Question 7

MVP allows for V-V cycle variations and occasional V-V pauses of what length?

Answer 7

• 2x the LR plus 80ms

Question 8

What does the MVP algorithm consider temporary loss of conduction?

Answer 8

when conduction loss occurs in 1 of the last 4 beats, stays in AAI(R)

Question 9

What does the MVP algorithm consider permanent loss of conduction?

Answer 9

when conduction loss occurs in 2 of the last 4 beats, switches to DDD(R)

Question 10

When and how does MVP know to switch back to AAI(R) from DDD(R)?

Answer 10

algorithm conducts periodic one cycle conduction checks starting 1 min after switching to DDD(R), then doubles time up to 16hrs, then checks every 16hrs

Question 11

What happens if the patient has MVP mode on and experiences AFib?

Answer 11

• device will mode switch to DDIR until the episode terminates, then switches to DDD(R)
• will perform a conduction check 1 min after switching to DDD(R) at termination of the episode

Question 12

During an AT/AF episode, Mode Switch will force the mode to DDIR from AAI(R), DDD(R) or both?

Answer 12

both AAI(R) and DDD(R)

Question 13

How often does MVP perform conduction checks?

Answer 13

• starts 1 minute after switching to DDD(R), then doubles in time for every failed test up to 16hrs, then q16hrs after
• 1, 2, 4,……16hrs, q16hr

Question 14

MVP can reduce RV pacing to what percentage/

Answer 14

< 5%

Question 15

What is the Atrial Refractory Period when the HR is < 75 bpm and the device is operating in MVP mode?

Answer 15

600 ms

Question 16

What is the Atrial Refractory Period when the HR is greater than or equal to 75 bpm when the device is programmed to MVP?

Answer 16

75% of the R-R cycle length

Question 17

What are the 3 MVP enhanced timing rules?

Answer 17

• dynamic Atrial Refractory Period (ARP)
  
  • HR < 75bpm -> ARP = 600ms
    (max ARP)
  • HR greater than or equal to
    75bpm -> ARP = 75% of R-R cycle
    length
• avoids inappropriate switches to DDD(R) with non-conducted PACs and FFRW
• A-A escape interval resets only after true P-waves

Question 18

How does a PVC affect the V-A interval when the device is operating in MVP mode?

Answer 18

• A PVC resets the V-A interval and causes the atrial escape interval to be re-calculated
• may appear to produce long A-A intervals, but this is normal operation

Question 19

What is MVPs response to a PVC or run of PVC?

Answer 19

• inhibits atrial pacing (no AP during PVC)
• resets V-A escape interval, which reschedules the next AP

Question 20

Which mode switch method/criteria does the MVP algorithm use to determine if an atrial tachyarrhythmia is in progress?

Answer 20

• 4 of 7 mode switch criteria
• if 4 of the last 7 A-A intervals are faster than the mode switch rate, device will mode switch to a non-tracking mode

Question 21

What are the 3 MVP 2.0 updates?

Answer 21

• can program a max AV interval and when the avg AV interval is greater than the programmed max AV interval limit, the device will mode switch
• reduced max V-V interval following onset of AV block
  
  • if the VS does not occur when expected based on the hx of recent of AV conduction events, MVP will pace the atrium (to preserve AV synchrony), then VP 80ms later
• reduces unnecessary mode switches to maintain AV synchrony at higher pacing rate

Question 22

Where can you see how many times MVP has switched the pacing mode?

Answer 22

Data-clinical diagnostics list -> MVP mode switches

Question 23

What are the 3 new features included in MVP 2.0?

Answer 23

• switches to DDD(R) when average AV interval is greater than programmed Maximum AV Interval Limit in pts with long AV delays
• reduces Maximum V-V interval following onset of AV block or PVC’s based on pts hx of conduction
• reduces unnecessary MVP mode switches in pts with unstable AV conduction or elevated pacing rates

Question 24

How does MVP 2.0 reduce the maximum VV interval following the onset of AV block or PVC’s?

Answer 24

Provides an AP followed by a VP 80ms after, if a VS does not occur within the expected VS window based on the pts hx of recent AV conduction events

Question 25

Why does MVP provide an AP prior to a VP if a VS does not occur within the expected VS window based on the pts hx of recent AV conduction events

Answer 25

To maintain AV synchrony and prevent retrograde conduction

Question 26

Where do you look to see how often MVP is switching the pacing mode for the patient?

Answer 26

-> Data-Clinical Diagnostics list -> MVP MODE SWITCHES -> shows the most recent 10 MVP mode switches with no EGM, but the number of total switches will be at the top ot the screen