Medtronic PROTECTA XT DR D314DRG, Руководство для клиницистов

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ARS is a programmable feature designed to prevent the long sinus pause that typically
follows a PAC. ARS responds to a PAC by instantly elevating the atrial pacing rate, then
smoothly slowing the rate back to the intrinsic rate or the programmed pacing rate
(whichever is faster). When activated by a PAC, the device delivers a pacing pulse at the
premature interval increased by a percentage of that interval (defined by a programmed
Interval Percentage Increment parameter). For each subsequent atrial paced or atrial
sensed event, the device continues to increase each pacing interval by the programmed
percentage of the previous interval. In this way, ARS prevents the “short-long-short”
sequences of atrial intervals that may precede the onset of some atrial tachyarrhythmias.
The Maximum Rate parameter sets an upper rate limit for ARS.
Atrial pacing pulses delivered for ARS are annotated on the Marker Channel with PP
(proactive pace).
Figure 119. Example of ARS operation
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R
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200 ms
ECG Lead I
Marker Channel
1 Pacing occurs at the programmed pacing rate.
2 A premature beat occurs followed by an ARS pacing pulse (indicated by the PP marker). The
pacing pulse is delivered at the AP-AR interval plus the programmed Interval Percentage
Increment value (25% in this example).
3 The device uses the AP-PP interval to calculate the subsequent ARS pacing interval.
4 Based on the programmed Interval Percentage Increment value, the ARS pacing interval is 25%
longer than the preceding one.
5 ARS pacing ends when the sensor rate or lower rate is reached.
Interactions with other device operations – ARS is suspended during mode switching
(including PMOP) and detected tachyarrhythmia episodes.
Note: Generally, when multiple device features attempt to control the pacing rate, the
feature with the fastest rate takes precedence.
Medtronic PROTECTA™ XT DR D314DRG
Clinician Manual 279