Medtronic PROTECTA XT DR D314DRG, Руководство для клиницистов

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Note: In DDI mode, Low Rate Detection occurs when the atrium or the ventricle is paced
at the Lower Rate for the programmed number of beats.
When both detection methods are programmed, the device intervenes when either Drop
Detection or Low Rate Detection criteria are met. For example, if the heart rate drops too
slowly to meet programmed Drop Detection criteria and continues to drop, the heart is
eventually paced at the Lower Rate. If this continues for the programmed number of
detection beats, the device intervenes.
7.8.2.2 Intervention and step-down
When a rate drop is detected, the device paces the heart at the programmed Intervention
Rate for the programmed Intervention Duration. After the Intervention Duration is complete,
the device reduces the pacing rate by 5 bpm steps per minute. This step-down process
continues until the sinus rate or the Lower Rate is reached.
Intervention pacing and step-down pacing are immediately ended when the device senses
3 consecutive nonrefractory atrial events.
Note: If the Lower Rate is reached at the conclusion of the step-down phase and Low Rate
Detection is programmed, the device does not detect another rate drop until it senses
evidence of a sinus rate that is above the programmed Lower Rate.
See Figure 105 for an example of the device detecting a rate drop and starting to pace the
heart at the programmed Intervention Rate.
Figure 105. Example of detection and intervention
EGM
Marker Channel
200 ms
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1 Normal sinus rhythm
2 Rate drop detected 3 Intervention pacing started
Medtronic PROTECTA™ XT DR D314DRG
Clinician Manual 259