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Stratos LV/LV-T Technical Manual  97 
When the Automatic Sensor Gain is activated, the CRT-P 
samples the sensor-indicated rate.  If, during the 24 hour period 
beginning at midnight, the total time recorded at maximum 
sensor rate exceeds 90 seconds, the sensor gain setting is 
reduced by one step.  The sensor gain will be increased by one 
step if for 7 consecutive days; the time recorded at maximum 
sensor rate is less than 90 seconds each day. 
2.14.4 Sensor Threshold 
The effects of rate adaptive pacing are limited to sensor signals 
exceeding the programmable sensor threshold.  Sensor signals 
below this threshold do not affect rate response (
Figure 7
).  The 
programmable sensor threshold ensures that a stable rate at 
rest can be achieved by ignoring sensor signals of low amplitude 
that are not related to exertion. 
If the pacing rate at rest is unstable, or tends to stay above the 
lower rate without activity, the sensor threshold should be 
increased.  The sensor threshold should be reduced if a 
sufficient rate increase is not observed at a given level of 
exertion. 
 
Figure 7  Effect of sensor threshold 
2.14.5 Rate Increase 
The rate increase parameter determines the maximum rate of 
change in the pacing rate if the sensor signal indicates 
increasing exertion.   
The “rate attack” is set to standard value of 2 ppm/cycle and is 
programmable (0.5; 1… (1)…6 ppm/cycle). 
The programmed rate increase applies only to the 
sensor-controlled operation and does not affect the rate changes 
during atrial-controlled ventricular pacing.