Example of MVP Mode of Pacemaker |
Case:
A 68-year-old male received dual chamber pacemaker sinus node dysfunction with syncope.
The pacemaker tracing shown below was obtained 4 weeks postimplant:
• Mode: AAIRóDDDR
• Pacing rate: 60 to 130 bpm
• Paced #AV delay: 200 ms
• Sensed AV delay: 170 ms
Why there variation in the AV delay?
The programmed mode is indeed #MVP, in which the device switches between #AAIR to DDDR depending on the presence of intrinsic R waves.
Managed Ventricular Pacing (MVP) is a pacing mode in some Medtronic pacemakers, ICDs, and CRT-D devices that reduces unnecessary right ventricular pacing.
In this mode, when the device is in AAIR and believes an atrial paced event is not followed by a ventricular sensed event, the device allows for this loss of conduction to occur once, and then follows with an atrial paced/ventricular paced event with a shortened paced AV delay of 80 ms The device then stays in AAIR mode and allows for an atrial paced event again with no ventricular intrinsic conduction.
If 2 of 4 events occur with no ventricular conduction, the device switches to DDDR mode. After 1 minute of DDDR, the device
will search for intrinsic conduction. If there is none, the device remains in DDDR mode for 2 minutes, rechecking again. This exponentially increases until the interval reaches 16 hours, at which time the device
will continue to check every 16 hours until the mode is reprogrammed.
Note that the paced QRS complexes in events 2, 6, and 8 with the shorter-paced AV delay of 80 ms result in a captured ventricular paced complex, while the longer paced AV delay of 200 ms in events 9 to 13
results in a slightly fused ventricular paced complex. This is because the shortened AV delay fully captures the ventricle, but the
longer AV delay allows intrinsic AV conduction resulting in fusion of the paced and sensed complexes.
Comments
Post a Comment
Drop your thoughts here, we would love to hear from you