Mintek Pacemaker LV-T ユーザーズマニュアル

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124  Stratos LV/LV-T Technical Manual   
To determine the threshold, the ECG must be observed 
continuously.  Based on the measured threshold, the pulse 
amplitude for the permanent program should be adjusted.  
Please consult the pertinent medical literature for specific 
recommendations regarding necessary safety margins. 
N
OTE
With successful biventricular pacing of patients with 
congestive heart failure, the QRS complex should be visibly 
shortened. 
5.2 
P/R Measurement - Testing the 
Sensing Function 
Stratos CRT-Ps provide a P-/R-wave test for measuring the 
amplitude of intrinsic events during follow-up examination.  The 
test determines the minimum, mean and maximum amplitude 
values over a programmable period of time.  In addition, these 
values may be printed out. 
To permit evaluation of the sensing function, the pacing rate 
must be lower than the patient's intrinsic rate.  In demand 
pacing, the proper sensing function can be recognized if the 
interval between intrinsic events and the following pacing pulse 
equals the basic interval (if no Hysteresis is programmed). 
For evaluation of the sensing function, the CRT-P features an 
intracardiac electrogram (IEGM) with marker signals to indicate 
sensed and paced events.  In addition, triggered pacing modes 
can be selected which, synchronously to the detection of an 
intrinsic event, emit a pacing pulse and mark the sensed event 
and its timing on the ECG. 
Especially with unipolar sensing functions, the selected 
sensitivity level should be checked for possible interference from 
skeletal myopotentials.  If oversensing is observed, the 
programming of a lower sensitivity (higher value), or bipolar 
sensing function, if the implanted lead is bipolar, should be 
evaluated.