User Manual Part 2

5-50
PACING THERAPIES
AV DELAY
Dynamic Sensed AV Delay and Paced AV Delay are based on the atrial rate. To
reflect the shortening of the PR interval during periods of increased metabolic
demand, the AV Delay shortens linearly from the programmed (maximum)
value at the LRL to a v alue determined by the ratio of minimum and maximum
AV Delay at the higher of the MTR or MSR (Figure 5-19 on page 5-50). When
Dynamic AV Delay is used, if the Sensed AV Delay value is progra mmed as
shorter than the maximum Paced AV Delay value, then the Sensed AV Delay
value will also be shorter than the minimum Paced AV Delay value at upper
rates.
Maximum
Paced AV
Delay
Minimum
Paced AV
Delay
Shorter of MTR
or MSR Interval
LRL Interval Hysteresis Rate
Interval
Paced AV Delay
Sensed AV Delay
Figure 5-19. Dynamic and Sensed AV Delay as a function of the escap e interval
NOTE: The min im um value is program mable only in VD D (R) mode.
SmartDelay Optimization
The SmartDelay optimization test uses atrial sensed and paced events to
determine suggested settings for the following:
• Paced AV Delay
• Sensed AV Dela y
• Ventricular Pacing Chamber
•LVOffset
These suggested settings can be used when programming the pulse generator
for CRT.
- DRAFT -