Transcript Document

Auto Mode Switch
Auto Mode Switch
• Changes to a non-tracking mode during high atrial rates
• Programmable Atrial Tachycardia Detection Rate
• Programmable post-ventricular atrial blanking (PVAB)
minimizes inappropriate mode switching due to far-field
R-waves
Auto Mode Switch
• Adapt Filtered Atrial Rate Interval (FARI) based on P-P
intervals
• The FARI decreases by 38 ms when P-P interval is
shorter than FARI
• The FARI increases by 25 ms when P-P interval is
longer than FARI
• FARI < ATDR interval: Entry Mode Switch
• FARI > Maximum Tracking Rate (sensor indicated rate
interval): Exit Mode Switch
Rate (bpm)
Interval (ms)
265
Atrium
278
200
ATDR
180
316
FARI < ATDR Interval:
mode switch entry
264
277
303
290
289
315
302
300
314
333
354
392
430
468
400
506
150
544
PP < FARI: -38 ms
582
620
PP > FARI: +25 ms
658
696
734
100
600
772
810
848
886
time to
mode switch
mode switch
entry
924
962
1000
50
0
1
1200
2
3
4
5
Time (sec)
6
7
8
9
10
Rate (bpm)
Interval (ms)
PP < FARI: -38 ms
300
200
300
325
350
180
PP > FARI: +25 ms
375
ATDR
333
400
425
150
400
450
475
MTR
120
FARI > MTR Interval:
500
500
mode switch exit
525
600
100
550
time to
mode switch
mode switch
exit
Atrium
1200
50
0
1
2
3
4
5
Time (sec)
6
7
8
9
10
Auto Mode Switch
Filtered Atrial Rate Interval (FARI)
Atrial cycle lengths
DDD
670ms
650ms
630ms
590ms
0ms
-38ms
-38ms
-38ms
670ms
670ms
632ms
ATDR: 180bpm
300ms
300ms
300ms
300ms
300ms
350ms
300ms
300ms
300ms
300ms
594ms
333ms
-38ms
-38ms
+25ms
-38ms
-38ms
-38ms
-38ms
-38ms
-38ms
518ms
556ms
FARI
DDI
442ms
480ms
366ms
404ms
328ms
290ms
315ms
600ms
600ms
+25ms
+25ms
277ms
302ms
327ms
+25ms
Auto Mode Switch Base Rate
Auto Mode Switch (AMS ) Base Rate Can
Be Programmed To:
• Base Rate + 0 ppm. to Base Rate + 35
ppm.
• (In Steps of 5 ppm.)
Auto Mode Switch Base Rate
Auto Mode Switch - AMS Base Rate