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Possible Technical Complications
Technical malfunctions
Technical device system malfunctions cannot entirely be excluded. Possible causes can
include the following:
• Lead dislocation
• Lead fracture
• Insulation defects
• Device component failures
• Battery depletion
Possible Electromagnetic Complications
Electromagnetic interference (EMI)
Any device can be sensitive to interference, for example, when external signals are
sensed as intrinsic rhythm or if measurements prevent rate adaptation.
• BIOTRONIK devices have been designed so that their susceptibility to EMI is
minimal.
• Due to the intensity and variety of EMI, there is no guarantee for safety. It is gener-
ally assumed that EMI produces only minor symptoms in patients - if any.
• Depending on the pacing mode and the type of interference, sources of interference
may lead to pulse inhibition or triggering, an increase in the sensor-dependent
pacing rate or asynchronous pacing.
• Under unfavorable conditions, for example during diagnostic or therapeutic proce-
dures, interference sources may induce such a high level of energy into the pacing
system that the cardiac tissue surrounding the lead tip is damaged.
Device behavior in case of EMI
In the case of electromagnetic interference or undesired myopotentials, the device
switches to asynchronous pacing for the duration of the time that the interference rate
is exceeded.
Static magnetic fields
The reed switch in the pacemaker starts to close at a field strength of 1.5 mT.
Possible Risks
Contraindicated procedures
The following procedures are contraindicated as they may cause harm to the patient or
damage the device and, as a result, put the system functionality at risk:
• Therapeutic ultrasound: Harm to the patient via excess warming of body tissue
near the device system
• Transcutaneous electrical nerve stimulation
• Hyperbaric oxygen therapy
• Applied pressures higher than normal pressure
Risky therapeutic and diagnostic procedures
If electrical current from an external source is conducted through the body for diag-
nostic or therapeutic purposes, then the device can be subjected to interference, which
can place the patient at risk.
Arrhythmia or ventricular fibrillation can be induced during diathermic procedures
such as electrocautery, HF ablation or HF surgery. For example, damaging heat levels
may arise during lithotripsy. Influences on the device are not always immediately clear.
If risky procedures cannot be avoided, the following should be observed at all times:
• Electrically insulate the patient.
• Switch the pacemaker function to asynchronous modes if needed.
• Do not introduce energy near the device system.
• Additionally check the peripheral pulse of the patient.
• Monitor the patient during and after every intervention.
External defibrillation
The device is protected against the energy that is normally induced by external defibril-
lation. Nevertheless, any implanted device may be damaged by external defibrillation.
Specifically, the current induced in the implanted leads may result in necrotic tissue
formation close to the electrode/tissue interface. As a result, sensing properties and
pacing thresholds may change.
• Place adhesive electrodes anterior-posterior or perpendicular to the axis formed
by the device to the heart at least 10 cm away from the device and from implanted
leads.
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