User's Manual
Table 9. Lead measurements (continued)
Pace/ sense lead (acute) Pace/ sense lead (chronic)
Lead impedance (at 5.0 V and 0.5
ms atrium and right ventricle)
> programmed Low Impedance
Limit (200–500 Ω)
< 2000 Ω (or the programmed
High Impedance Limit
(2000–3000 Ω))
> programmed Low Impedance
Limit (200–500 Ω)
< 2000 Ω (or the programmed
High Impedance Limit
(2000–3000 Ω))
Lead impedance (at 5.0 V and 0.5
ms left ventricle)
> programmed Low Impedance
Limit (200–500 Ω)
< 2000 Ω (or the programmed
High Impedance Limit
(2000–3000 Ω))
> programmed Low Impedance
Limit (200–500 Ω)
< 2000 Ω (or the programmed
High Impedance Limit
(2000–3000 Ω))
a. Amplitudes less than 2 mV cause inaccurate rate counting in the chronic state, and result in inability to sense a
tachyarrhythmia or the misinterpretation of a normal rhythm as abnormal.
b. Lower R-wave amplitudes and longer duration may be associated with placement in ischemic or scarred tissues. Since signal
quality may deteriorate chronically, efforts should be made to meet the above criteria by repositioning the leads to obtain
signals with the largest p ossible amplitude and shortest duration.
c. Durations longer than 135 ms (the pulse generator’s refractory period) may result in inaccurate cardiac rate determination,
inability to sense a tachyarrhythmia, or in the misinterpretation of a normal rhythm as abnormal.
d. This measurement is not inclusive of current of injury.
If the lead integrity is in question, standard lead troubleshooting tests should be used to assess the lead system
integrity. Troubleshooting tests include, but are not limited to, the following:
• Electrogram analysis with pocket manipulation
• X-ray or fluoroscopic image review
• Invasive visual inspection
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