User Manual Part 1

TACHYARRHYTHMIA DETECTION
VENTRICULAR DETECTION
3-35
0 s 5 s 35 s
0 s
30 s
Duration = 5 seconds
SRD = 30 seconds
Evaluate programmed detection
enhancements. If enhancements
indicate to inhibit therapy, start
SRD timer; otherwise, deliver
therapy.
Continue detection
enhancement
analysis throughout
SRD time.
If detection
enhancements
indicate therapy,
deliver therapy.
SRD times out.
Deliver therapy.
Detection window
satisfied
Duration starts. Start
detection enhancement
analysis.
Duration expires.
Figure 3-21. Comb ina tion of Onset OR Stability, SRD programmed on
SRD is available in a zone only when an inhibitor enhancement is programmed
on in that zone. When the Rhythm ID detection enhancement suite is enabled,
SRD may be programmed separately for the VT and VT-1 zones.
• If an inhibitor is withholding ventricular therapy delivery and the Rate
criterion in the lowest zone is main ta ined, the programmed SR D time r
begins at the end of the first zone’s completed Duration.
• If the detection window in the lowest zone is maintained for the programmed
SRD period, the programmed v entricular therapy will be delivered at the
end of the VT-1 SRD period if VT-1 SRD is programmed and the rhythm
is in the VT-1 zone. Therapy will be delivered at the end of the VT SRD
period if VT SRD is programmed and the rhythm is in the VT zone.
• If the rate accelerates to a higher ventricular zone, detection enhancements
are not programmed to On in the higher zone, and the Duration for the
higher zone expires, therapy is initiated in that zone without waiting for
SRD time-out in a lower ventricular zone. If SRD is programmed to Off,
an SRD timer will not start whe n Duration ex pires, thus allowing detection
enhancements to potentially inhibit therapy indefinitely.
An independent Post-Shock SRD value may be programmed.
Combinations of AFib Rate Threshold, Stability, and Vector Timing and
Correlation
The combinatio n of AFib Rate Threshold, Stab ility, and Vector Timing and
Correlation add specificity to ventricular detection beyond rate and duration.
In addition to using AFib Rate Threshold and Sta bility to identify AF, this
combination of enhancements uses Vector Timing and Correlation analysis
to differentiate SVT rhythms from VT rhythms based on conduction patterns
within th e heart.
- DRAFT -