9.5.4 Parameter Interaction
In order to avoid false event detections, the CCM signal has to be delivered
entirely within the right atrial and right ventricular refractory period. Prior to the
end of these refractory periods, an 86 ms long noise window is activated to detect
external interference. Therefore, CCM signal delivery has to be completed before
the noise window is opened. This is accomplished with the following constraint:
• The sum of the values Alert Start, Alert Width, CCM Delay, and CCM
Train Total Duration must be smaller than the lower of the following two
values: right atrial refractory period, right ventricular refractory period
minus 86 ms.
If the V channel is used for CCM signal delivery, the balancing phase also needs
to be completed before the noise window starts. This can be guaranteed by the
following constraint:
• If the V channel is used for CCM signal delivery, the sum of the values
Alert Start, Alert Width, CCM Delay, CCM Train Total Duration, and
Balancing Phase (40 ms) needs to be smaller than the lower of the
following two values: right atrial refractory period, right ventricular
refractory period minus 86 ms.
The Alert Start time relates to the right ventricular event. Thus, if the Alert Start
value is negative and if a local sense event is detected during the AV interval, a
right ventricular event will have to occur and be detected before the device can
determine if the event fell inside the alert window. That implies that the
OPTIMIZER Smart IPG cannot deliver a CCM signal prior to the right ventricular
event occurring. This is asserted by the following constraint:
• The sum of Alert Start and CCM Delay must be equal to or greater than
3 ms
9.6 CCM Inhibit Parameters
By analyzing the train of sensed cardiac events based on their succession and their
temporal order, the OPTIMIZER Smart IPG “decides” for each heart action whether to
deliver CCM signals or not.
9.6.1 Number of Beats for CCM Inhibition
For the period when CCM signal delivery is inhibited, one can program the
number of beats for which CCM signal delivery will continue to be inhibited after
the initial inhibiting event. With the OMNI Smart Programmer software, the total
number of inhibited beats can be set to any value between 1 and 16. This means
that CCM delivery can be inhibited from to none to 15 additional beats beyond
the beat leading to the initial inhibiting event.
Please note that this number of inhibited cycles applies to the most current event
leading to signal inhibition, i.e. a new inhibiting condition occurring during a
period of already inhibited CCM signal delivery will start a new inhibition period.
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