MVP Flashcards
What does MVP stand for?
Managed Ventricular Pacing
How does MVP work?
- 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
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?
program the lower rate to 50bpm or higher prevents long V-V interval pauses
What is required for the mode to remain in AAI(R) mode while programmed to MVP?
- 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
When is MVP programming not appropriate?
- for patients with symptomatic 1st degree AV block
- complete heart block
- symptomatic rate-dependent AV block
- suspected pause-dependent VT with no ICD backup
When will MVP provide a backup VP?
- 80ms after the next schedule AP or A-A escape interval
MVP allows for V-V cycle variations and occasional V-V pauses of what length?
- 2x the LR plus 80ms
What does the MVP algorithm consider temporary loss of conduction?
when conduction loss occurs in 1 of the last 4 beats, stays in AAI(R)
What does the MVP algorithm consider permanent loss of conduction?
when conduction loss occurs in 2 of the last 4 beats, switches to DDD(R)
When and how does MVP know to switch back to AAI(R) from DDD(R)?
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
What happens if the patient has MVP mode on and experiences AFib?
- 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
During an AT/AF episode, Mode Switch will force the mode to DDIR from AAI(R), DDD(R) or both?
both AAI(R) and DDD(R)
How often does MVP perform conduction checks?
- 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
MVP can reduce RV pacing to what percentage/
< 5%
What is the Atrial Refractory Period when the HR is < 75 bpm and the device is operating in MVP mode?
600 ms
What is the Atrial Refractory Period when the HR is greater than or equal to 75 bpm when the device is programmed to MVP?
75% of the R-R cycle length
What are the 3 MVP enhanced timing rules?
- 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
- HR < 75bpm -> ARP = 600ms
- avoids inappropriate switches to DDD(R) with non-conducted PACs and FFRW
- A-A escape interval resets only after true P-waves
How does a PVC affect the V-A interval when the device is operating in MVP mode?
- 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
What is MVPs response to a PVC or run of PVC?
- inhibits atrial pacing (no AP during PVC)
- resets V-A escape interval, which reschedules the next AP
Which mode switch method/criteria does the MVP algorithm use to determine if an atrial tachyarrhythmia is in progress?
- 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
What are the 3 MVP 2.0 updates?
- 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
Where can you see how many times MVP has switched the pacing mode?
Data-clinical diagnostics list -> MVP mode switches
What are the 3 new features included in MVP 2.0?
- 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
How does MVP 2.0 reduce the maximum VV interval following the onset of AV block or PVC’s?
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
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
To maintain AV synchrony and prevent retrograde conduction
Where do you look to see how often MVP is switching the pacing mode for the patient?
-> 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