1. What are the 3 methods of VF induction?
    • Shock on T
    • Burst Pacing
    • AC/DC Fibber
  2. What is shock on T?
    1-2J shock on a T wave
  3. What is Burst pacing induction of VF?
    Pace at 300bpm
  4. What is CD fibber?
    Shock directly into myocardium
  5. What are the detection RATE criteria that need to be met for an ICD to detect a nasty arrthymia?
    • Beat-Beat intervals
    • Beats per minute i.e ranges
    • Classifies rhythm by detection zone
  6. What are the detection DURATION criteria that need to be met for an ICD to detect a nasty arrthymia?
    • Number of intervals
    • Length of time in rhythm
  7. What is consecutive rate duration criteria?
    Number of simultaneous beats i.e 16 in a row
  8. What is probabilistic detection duration?
    Percentage or fraction i.e 12/16beats
  9. What rhythm is consecutive criteria used for?
  10. What rhythm is probabilistic criteria used for?
  11. What do detection "zones" allow?
    Allow discrimination between VT and VF based on cycle length
  12. Fast VT (FVT) can also be set: What are the detection durations for FVT via VT and FVT via VF?
    • FVT via VT - Consecutive
    • FVT via VF - Probabilitic
  13. Which therapy is best designed for VT?
    Anti-Tachy Pacing (ATP)
  14. Which therapy is best designed for FVT?
  15. Which therapy is best designed for VF?
  16. What is SVT discriminators used for?
    Prevent detection of tachyarrhythmias caused by SVTs - preventing inappropriate therapy
  17. What is waveform morphology?
    ICD detects the normal waveform and uses it as a template for distinguishing normal and abnormal rhythms
  18. How does an ICD use SVT Discriminators?
    • Waveform Morphology
    • EGM width
    • Wavelet threshold template
    • Onset (gradual/sudden - calculates average)
    • Stability (regular/irregular)
    • Dual chamber synchrony i.e. PR logic
  19. What is ATP and what arrhythmias can it eliminate?
    • Pacing pulses delivered at higher rate in comparison to the detected rhythm
    • Terminate re-entry tachys (VT)
  20. How does ATP work electrically? HOw does distance effect the efficiency?
    • ATP pulses bombard reentry circuit until the pulses refracts the circuit causing it to break
    • The further away the electrode is from the circuit means its less efficient
  21. What are ATPs programmable:
    • Sequences: Number of times ATP will be applied upon re-detection
    • Pulses: Number of pulses per sequence
  22. What is an ATP burst?
    • Series of pacing pulses delivered at equal intervals
    • Intervals decrement per sequence
  23. What is an ATP ramp?
    • Series of pacing pulses delivered at ever decreasing intervals
    • Pulse added per sequence
  24. What is burst+?
    Burst therapy followed by 2 individually programmable pulses
  25. What is Ramp+?
    2 stimuli at individually programmable intervals, followed by a burst therapy
  26. What is the shortest interval for ramp or burst?
  27. Why is ATP always initiated first?
    • Low Power
    • Painless
    • Less Risk
    • Done during charge
  28. Which part of the QRS complex is the cardioversion shock delivered to?
    R wave
  29. What is a defibrillation shock?
    Shock delivered to the heart to terminate a tachyarrhythmia
  30. How does device see therapy success?
    8 normal beats
  31. Why is biphasic waveforms more appropriate for therapy?
    • Lower thresholds
    • Higher success rate
    • Reduced myocardial injury
    • Faster sinus rhythm restoration post shock
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