BIOTRONIK Evia DR, Техническое руководство

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Evia Technical Manual 55
7.1.4 Mode Switching
Evia provides Mode Switching to change pacing modes as a
result of atrial tachycardias. Mode Switching is designed to
avoid tracking of non-physiologic atrial rates due to paroxysmal
atrial tachycardias (PATs). Mode Switching is only available in
atrial tracking modes DDD(R), VDD(R), and DDD-CLS
Mode Switching
The Mode Switching algorithm causes the pulse generator to
change pacing modes when a programmed number of atrial
intervals (X) out of 8 consecutive atrial intervals (p-p) are faster
than the programmed mode switch intervention rate (X out of 8).
X is programmable from 3 to 8. The rate at which an atrial
interval is determined to signify an atrial tachyarrhythmia is
called the mode switch intervention rate. The mode switch
intervention rate is programmable from 100 to 250 bpm. A Mode
Switch Basic Rate can be programmed to allow for a higher
basic rate during an active Mode Switch, in order to diminish
undesirable hemodynamic behaviors.
The mode switch occurs from atrial tracking to non-atrial tracking
pacing modes (e.g. DDDR to DDIR) as described in
Table 13
.
Reversion back to the programmed pacing mode occurs in a
similarly programmable manner. If a programmable number of
atrial intervals (Z) out of 8 consecutive atrial intervals (p-p) are
slower than the programmed mode switch intervention rate
(Z out of 8), the device will revert back to the permanently
programmed parameters. Z is programmable from 3 to 8. The
device will also revert back to the permanent program if no atrial
paced or sensed events have occurred for at least 2 seconds.
Additionally, during DDI(R), the AV-delay is set to 100 ms.
Mode Switch Events are recorded in memory and are available
to the user through the following diagnostics:
•
IEGM Recordings Found in the Holter Tab
•
Mode Switch Counter
•
Total Mode Switch Duration
Mode Switching is available during magnet application after 10
cycles of ASYNC pacing and during ERI. Mode Switching occurs
as described in
Table 13
.