User's Manual

59
Pacing and Sensing Functions
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If the impedance lies outside of this range, the implant switches to
unipolar pacing. A unipolar lead is then confirmed.
Any sense event occurring during the phase for recognizing lead
polarity triggers a stimulus in the same chamber. This allows the
impedance to be measured.
The Confirmation Phase
After successful lead detection and detection of the lead polarity, an
implantation confirmation time of 30 minutes is started. Upon each
stimulus, the prior detected status must be confirmed. If this occurs,
lead recognition is successfully concluded.
The pacing pulse is as a rule inhibited when there are intrinsic cardiac
events. If intrinsic cardiac events are detected during the confirmation
phase, a stimulus is triggered every 10 minutes in the atrium and
ventricle to determine the lead impedance.
If there is no confirmation of the prior detected status, the initial lead
detection is restarted.
Auto-Initialization
Purpose
A few implant functions are automatically activated by the auto-
initialization function. A prerequisite is the successful detection and
confirmation of the connected leads (in both chambers in the case of
dual-chamber implants).