User's Manual

Table Of Contents
Step G: Evaluate Lead Signals
1. Take the pulse generator out of power-saving Storage mode by programming the Tachy Mode to Off.
CAUTION: To prevent inappropriate shocks, ensure that the pulse generator’s Tachy Mode is programmed to
Off when not in use and before handling the device. For tachyarrhythmia detection and therapy, verify that the
Tachy Mode is programmed to Monitor + Therapy.
2. Evaluate the pace/sense and debrillation lead signals by viewing the real-time EGMs and markers. The
signal from the implanted debrillation leads should be continuous and without artifact, similar to a
body-surface ECG. A discontinuous signal may indicate a poor connection, lead fracture or otherwise
damaged lead, or an insulation break that would necessitate lead replacement. Inadequate signals may
result in failure of the pulse generator system to detect an arrhythmia, inability to deliver programmed
therapy, or unnecessary delivery of therapy. Lead measurements should reect those above (Table 8 on
page 51).
CAUTION: Take care to ensure that artifacts from the ventricles are not present on the atrial channel, or
atrial oversensing may result. If ventricular artifacts a re present in the atrial channel, the atrial lead may
need to be repositioned to minimize its interaction.
3. Evaluate all lead impedances.
CAUTION: If total shocking lead impedance during implant is less than 20 , verify the proximal coil is not
in contact with the pulse generator surface. A measurement of less than 20 is an indication of a short
somewhere in the system. If repeated measurements show the total shocking lead impedance is less than
20 , the lead and/or pulse generator may need to be replaced.
CAUTION: Patients should be tested for diaphragmatic stimulation by pacing the LV lead through the pulse
generator at 7.5 V and adjusting the lead congurations and lead position as necessary. PSA testing at higher
outputs (e.g., 10.0 V) may also be considered to better characterize stimulation margins. The probability
of diaphragmatic stimulation increases when a pacing system includes an LV lead because of this lead’s
proximity to the phrenic nerve.
59