User Manual Part 2

B-1
PACEMAKER INTERACTION
APPENDIX B
There may be instances where patients may have a separate temporary or
permanent pacemaker. Temporary or permanent pacemakers can interact
with an ICD and can interfere with th e ide ntification of tachyarrhythmias in
the following ways:
• During a tachyarrhythmia, if the pacemaker does not sense the arrhythmia
and paces, and the pacing pulse detected from the ICD rate-sensing
electrode is large enough, it c ould cause the ICD to interpret the pacing
as a normal rhythm at the rate of the pacemaker. The ICD would neither
detect the arrhythmia nor deliver therapy.
• The pacemaker could present signals to the ICD resulting from the
following events:
– Inappropriate sensing
– Lead dislodgment
– Failure to capture
This could cause the ICD’s rate measurement to be faster than the patient’s
actual heart rate. As a result, the ICD could deliver inappropriate therapy.
• Conduction delay could cause the ICD to count both pacemaker artifact and
ventricular depolarization. This could result in inappropriate ICD therapy.
For these reasons, the use of a pacemaker that results in pacemaker and ICD
interaction is not recommended. Unipolar pacemakers are contraindicated for
usewithanICD.
Consider the following actions if a separate pacemaker is used:
• Always deactivate a patient’s ICD when:
– Using temporary bipolar or temporary AV sequential pacing
– Reprogramming a separate implanted pacemaker
If cardioversion or defibrillatio n is neede d at such times, use an e xternal
defibrillato r.
- DRAFT -