Medtronic PROTECTA XT DR D314DRG, Clinician Manual

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Figure 66. Comparison of the PVAB methods
AS
AS
AS
Ab
VS
VS
VS
Marker Channel
PVAB Interval
Marker Channel
Marker Channel
A. Sense EGM
A. Sense EGM
Sensing threshold
A. Sense EGM
Partial PVAB
PVAB
Absolute PVAB
1 When the Partial PVAB method is used, if the far-field R-wave exceeds the atrial threshold, an
Ab marker indicates that the event is sensed during the PVAB interval.
2 With the PVAB method, after a ventricular sensed or paced event, the atrial sensing
threshold increases, and the device is less sensitive to atrial events.
3 When the Absolute PVAB method is used, an atrial event is blanked in the PVAB interval whether
or not the far-field R-wave exceeds the atrial threshold.
4 Except for the change in the atrial sensing threshold, the PVAB and Partial PVAB
methods are similar. With either method, atrial events sensed in the PVAB interval are used by
the tachyarrhythmia detection features.
7.1.5 Operation of refractory periods
During a refractory period, the device senses normally but classifies sensed events as
refractory and limits its response to these events. The pacing refractory periods prevent
inappropriately sensed signals, such as far-field R-waves or electrical noise, from triggering
certain pacing timing intervals. Pacing refractory periods do not affect tachyarrhythmia
detection.
Medtronic PROTECTA™ XT DR D314DRG
206 Clinician Manual