Atrial Detection and Therapies Flashcards
For detection of ventricular arrhythmias, how does PR Logic determine AF?
If the AF evidence counter in >/= 6, this criterion is satisfied. If AF counter remains at >/= 5, the counter remains satisfied.
When does a device with atrial detection mode switch?
At onset; when the AT/AF evidence counter reaches 3, which usually takes 2-3 seconds.
What does atrial detection for therapy require?
Median atrial cycle length must be in the detection zone, AT/AF evidence counter must reach 32.
What type of counter is the AT/AF evidence counter?
Up/down
What happens after detection has been reached?
Episode duration. 0-24 hrs. Nominal 1 minute. This feature gives the arrhtyhmia a chance to break on it’s own before therapy is delivered.
How does redetection work for atrial therapies?
After therapy is delivered, AT/AF evidence counter returns to zero.
What is the termination criteria for an atrial episode?
Five sinus beats or sinus rhythm consistent with FFRW.
What therapies are available for terminating atrial arrhythmias?
Ramp, Burst +, 50 Hz, Cardioversion, Reactive ATP
What is atrial Burst +?
Burst train followed by two premature pulses.
What is atrial Ramp?
Decrements between each pulse and adds one pulse to each sequence.
What is atrial 50 Hz?
Delivers a train of 20 ms pulses.
What is reactive ATP?
A feature that allows for multiple deliveries of ATP therapy if rate or rhythm changes occur.
How does reactive ATP work?
The programmed AT/AF zone is divided into ten sub-zones or bins. Therapy for the entire zone is then applied to each bin, so that if the rate or rhythm changes, ATP will still be available. There is also a timeout feature where all ATP therapies will be replenished after a certain amount of time.
What is the Stop Rx After feature?
This feature will stop therapy if there is an atrial lead issue or after a programmable amount of time.
How does reactive ATP work when two zones are programmed?
There will be only one set of therapies for the Fast AT zone and the same binning system for the slower AT zone.
