ATP Before/During Charging

Question 1

When is ATP during charging delivered?

Answer 1

at detection of an VT/FVT episode while the capacitor is charging

Question 2

Preventing charging of a shock will save how many days of longevity on the battery?

Answer 2

approximately 32 days

Question 3

What happens after ATP before charging is delivered?

Answer 3

• the device begins counting for redetection to determine if the episode has ended
• if not, charging begins and ATP during charging is delivered
• if still not terminated, shock is delivered once CE

Question 4

What is the nominal setting for the “Deliver ATP if last 8 R-R >=”?

Answer 4

• 240ms, but is programmed to 200ms to deliver ATP at greater rates

Question 5

What algorithm switches to ATP before charging after a programmable number of successful ATP during charging sequences?

Answer 5

Charge Saver

Question 6

What does the Charge Saver algorithm do?

Answer 6

• switches to ATP before charging after a programmable number of successful ATP during charging sequences
• will see message in observation window of the switch

Question 7

What algorithm switches from ATP before charging to ATP during charging after 2 unsuccessful ATP before charging sequences?

Answer 7

Switchback

Question 8

What does the Switchback do?

Answer 8

switches from ATP before charging to ATP during charging after 2 unsuccessful ATP before charging sequences

Question 9

How many unsuccessful attempts are needed for the switchback feature to switch from ATP before charging to ATP during charging?

Answer 9

2 unsuccessful ATP before charging sequences

Question 10

How many unsuccessful attempts are needed for the Charge Saver to switch from ATP during charging to ATP before charging?

Answer 10

• is a programmable value nominally set to 1

Question 11

What does the Smart Mode feature do?

Answer 11

turns off ATP therapies after 4 unsuccessful attempts, 4 delivered shocks

Question 12

How many unsuccessful ATP before/during charging sequences are need for the Smart Mode feature to turn off ATP therapies?

Answer 12

4 unsuccessful ATP before charging sequences

Question 13

Which algorithm turns off ATP therapies after 4 unsuccessful attempts, 4 delivered shocks?

Answer 13

Smart Mode

Question 14

The energy level for VF therapy #1 should be set to what value and why?

Answer 14

• 20J or greater to allow enough time for ATP during charging to delivered and for the device to determine if it was successful prior to shocking

Question 15

What is the purpose of the setting “Deliver ATP if last 8 R-R >=”?

Answer 15

• this programmable value dictates the max rate that ATP will be delivered
• if any of the last 8 R-R intervals are faster/smaller than this value, ATP will be avoided and a shock will be delivered

Question 16

What are the programmable options for Charge Saver?

Answer 16

• on, off, number of successful ATP sequences

Question 17

Where can you see that ATP switch from Before to During charging?

Answer 17

• observations window
• parameters screen under “Therapies”
• the EGM episode