User Manual

Special case:
In triggered mode (single or dual chamber), the device may exceed the maximum tracking
rate and pace to the rate limit value.
Rate hysteresis
Rate hysteresis determines the ability of the patient’s natural sinus rhythm to decrease below
the escape rate. After sensing, the pacemaker operates with an escape rate reduced by the
programmed percentage of hysteresis.
Programming requirements:
1. If the Rate Response function is programmed, the escape rate cannot be below 50 ppm.
2. When the basic rate is less than or equal to 45 ppm, rate hysteresis is programmed to
0% and is not accessible.
NOTE: For the DR model: When Dplus mode is selected, the suggested percentage of
hysteresis is 20%.
PACING AND SENSING PARAMETERS
Pulse amplitude
The pulse amplitude determines the voltage applied to the heart during pacing.
Recommendation:
Use the “as shipped” value (or a higher value if required) immediately after implant to avoid
loss of capture due to the early rise in threshold. After threshold stabilization, a setting that
provides a suitable safety margin (twice the chronic threshold) and saves the pacemaker
battery can be found.
For the DR model, pulse amplitude is programmed independently for atrial pacing and
ventricular pacing.
Pulse width
The pulse width determines the duration for which the pulse amplitude is applied to the heart
during pacing.
Pulse width can be used to adjust pacemaker output.
For the DR model, pulse width is programmed independently for atrial pacing and ventricular
pacing.
Programming requirements:
When the Ventricular Autothreshold function is programmed to "Monitor" or "Auto", the
programmable ventricular pulse width is less than or equal to 0.5 ms.
For the DR model, when the Atrial Autothreshold function is programmed to "Monitor" or
"Auto", the programmable atrial pulse width is less than or equal to 0.5 ms.
15.2.3.
15.3.
15.3.1.
15.3.2.
15. FUNCTIONS AND PARAMETERS
38 ALIZEA – UA10414A