Medtronic PROTECTA XT DR D314DRG, Руководство для клиницистов

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9.2.2.1 Ventricular ATP therapy pacing rate
The ATP pacing interval is based on the ventricular tachycardia cycle length, which is
calculated as the average of the last 4 ventricular intervals prior to VT or FVT detection (or
redetection). The programmable parameter V-V Minimum ATP Interval limits the pacing
interval at which the ATP pulses are delivered within a sequence. If the ATP pacing interval
is shorter than the programmed V-V Minimum ATP Interval, the pulses are delivered at the
programmed V-V Minimum ATP Interval.
If the intrinsic ventricular tachycardia interval is shorter than or equal to the programmed
V-V Minimum ATP Interval, the device skips the rest of the ATP therapy and delivers the
first programmed cardioversion therapy. If no cardioversion therapy is programmed, no
therapy is delivered.
If the intrinsic ventricular tachycardia interval is longer than the programmed V-V Minimum
ATP Interval, but all the intervals of an ATP therapy sequence have been delivered at the
V-V Minimum ATP Interval, the device skips the rest of the ATP therapy and delivers the
next programmed ATP or cardioversion therapy. If the device detects an FVT episode, it
delivers the next programmed cardioversion therapy.
9.2.2.2 Burst pacing therapy
The programmable parameter Initial # Pulses sets the number of pulses in all sequences of
a Burst therapy. R-S1 Interval=(%RR) and Interval Dec are programmable parameters that
control Burst pacing intervals.
The first Burst sequence is delivered at a pacing interval determined by the R-S1
Interval=(%RR) parameter, as a percentage of the ventricular tachycardia cycle length.
Each pulse in the sequence is delivered at the same pacing interval. Each time the
ventricular tachycardia is redetected after an unsuccessful sequence, the device applies
the programmed Burst percentage to the new ventricular tachycardia cycle length. It then
subtracts the Interval Dec value (once per sequence) to determine the pacing interval of the
next Burst sequence.
Note: Burst pacing therapy is delivered in the VOO pacing mode.
In the example of Burst pacing operation in Figure 190, two Burst therapy sequences are
delivered. The second therapy sequence terminates the VT episode.
Medtronic PROTECTA™ XT DR D314DRG
370 Clinician Manual