22
Implantation
Preventing conduction of
atrial tachycardia
BIOTRONIK devices feature several functions to prevent conduction of atrial tachy-
cardia to the ventricle(s):
•
Set mode switching for indicated patients.
•
Set the upper rate and the refractory periods to prevent abrupt ventricular rate
switching.
•
Give preference to Wenckebach response and avoid 2:1 behavior.
•
Set all parameters so as to prevent constant changing between atrial and ven-
tricular-controlled modes.
Observing the shock imped-
ance limit
The implanted device could be damaged if the shock impedance is too low.
•
The shock impedance must be > 25 Ω.
Preventing recurrence
after therapy shock
After a therapy shock, pacing can be performed with a post-shock program if there
is no intrinsic rhythm.
•
The following post-shock program parameters can be adjusted: post-shock
duration, basic rate, rate hysteresis, ventricular pacing, LV-T-wave protection,
triggering, AV delay (fixed, not dynamic).
•
The default settings for the post-shock program are as follows:
A and RV: 7.5 V, 1.5 ms
LV: settings from the permanent program
Phrenic nerve stimulation
that cannot be terminated
In rare cases, chronic phrenic nerve stimulation cannot be terminated by repro-
gramming of the available left ventricular pacing configurations or by other mea-
sures.
•
As the case may be, set a right ventricular mode both in the permanent
program as well as the ATP, in the post-shock program and for
mode switching.
Avoiding risks in the case of
exclusive LV pacing
Lead dislodgement in the case of exclusive left ventricular pacing could pose the
following risks: loss of ventricular pacing and ATP therapy, induction of atrial
arrhythmias.
•
Consider sensing and pacing parameters with reference to loss of therapy.
•
Exclusive LV pacing is not recommended for patients who depend on the device.
•
Take non-availability of automatic active capture control into consideration.
•
In the case of follow-ups and threshold tests, take loss of synchronized ventric-
ular pacing into consideration.
•
Mode switching and post-shock do not allow for exclusive LV pacing. Also take
the effects into account when setting the mode switching and post-shock
parameters.
Recognizing lead failure
Automatic impedance measurement is always switched on.
•
Impedance values that indicate technical failure of a lead are documented in
the event list.
Permanent program
Post-shock program
DDD, DDI, AAI
DDI
VDD, VDI
VDI
VVI and OFF
VVI
