Shocking lead impedance readings between 20
Ω
and the programmed High Impedance Limit are considered
in-range. If abrupt or large impedance
fl
uctuations or out-of-range conditions are observed, consider the
following:
•
Verify the con
fi
guration—ensure the programmed Shock Vector matches the con
fi
guration of the
implanted lead (e.g., use RV Coil to Can with a single-coil lead).
•
Verify the connection—ensure the shocking lead’s terminal pins are placed in the correct lead ports
and verify a secure lead connection.
•
Verify the contact—ensure the device is inside a wet implant pocket since the pulse generator case
serves as an active electrode in the V-TRIAD con
fi
guration. Avoid pocket manipulation during the test.
•
Turn off sources of external noise (e.g., electrocautery equipment, monitors).
•
Use other troubleshooting tools, as needed, to further assess lead system integrity, including electrogram
analysis, X-ray or
fl
uoroscopic image review, or internal visual inspection.
NOTE:
Because this device uses a subthreshold test pulse to conduct shock lead impedance measurements,
it can be dif
fi
cult to measure responses to test signals when electrical interference or “noise” (e.g.,
electrocautery or external monitoring equipment attached directly to the patient) is present during the test. This
may result in impedance measurement variations, particularly at implant. In the absence of such electrical
interference, shock lead impedance readings will be more stable.
Step H: Program the Pulse Generator
1.
Check the Programmer Clock and set and synchronize the pulse generator as necessary so that the
proper time appears on printed reports and PRM strip chart recordings.
2.
It may be useful to program the Beep During Capacitor Charge feature to On during conversion testing
and implantation to help recognize when the pulse generator is charging to deliver a shock.
3.
Perform a manual capacitor re-formation if not already performed.
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