BIOTRONIK Lumax DR ICD Series, Техническое руководство, Страница: 97 / 176

Lumax Technical Manual 89
In addition to selecting the preset values ( Low, Medium, and
High ) with the Dynamic AV Delay window, the Dynamic
AV Delays may be programmed individually ( Individual ) for each
rate zone or to a fixed AV Delay ( Fixed ).
The AV Delay feature includes an AV Delay shortening option
(
Sense Compensation ) for dual chamber pacing modes. When
enabled, the AV Delay is shortened by the programmed value
(5 to 60 ms) from the programmed AV Delay after an intrinsic
atrial sensed event.
The Dynamic AV Delay is intended to mimic physiologic-
shortening of the AV Delay with increasing heart rate. It also
serves for automatic prevention and termination of “circus
movement” pacemaker mediated tachycardia and for prevention
of reentrant supraventricular tachycardias. Dynamic AV Delay is
available with the Lumax DR-T and HF-T ICDs/CRT-Ds.
2.9.5.1 Positive AV Hysteresis
Positive AV Hysteresis allows a user-programmable change in AV
delay that is designed to encourage normal conduction of intrinsic
signals from the atrium into the ventricles. With Positive AV
hysteresis enabled, the AV delay is extended by a defined time
value after sensing a ventricular event (10 … (10) …150 ms).
The long AV interval is used as long as intrinsic ventricular activity
is detected. The programmed short AV delay interval resumes
after a ventricular paced event.
2.9.5.2 AV Repetitive Hysteresis
With AV Repetitive Hysteresis, the AV delay is extended by a
defined hysteresis value after sensing an intrinsic ventricular
event. When a ventricular paced event occurs, a long AV delay is
used for the programmed number of cycles. (OFF, 1 … 10). If an
intrinsic rhythm occurs during one of the repetitive cycles, the
long duration AV delay interval remains in effect. If an intrinsic
rhythm does not occur during the repetitive cycles, the original AV
delay interval resumes.