Quiz

10 things you need to know about RYTHMIQ (Boston Scientific)

  1. the device provides AAI(R) pacing at the lower rate limit and/or sensor indicated rate
  2. the device provides backup VVI pacing at a rate of 15 bpm slower than the programmed lower rate limit
  3. the backup VVI pacing rate is limited to no slower than 30 bpm and no faster than 60 bpm
  4. switch from ADI/VVI backup to DDD mode is not based on the presence of blocked P waves but on the presence of slow ventricular beats
  5. two types of ventricular beats are considered slow: a paced ventricle and a sensed ventricular event with an interval greater than 150 ms relative to the programmed lower rate limit or current rate response
  6. the device automatically switches to DDD(R) mode if 3 ventricular beats are considered slow in a rolling window of 11 consecutive ventricular beats
  7. after a switch to DDD(R) mode, the device uses the AV Search+ algorithm to periodically search for the return of intrinsic conduction
  8. the AV Search+ algorithm corresponds to an AV delay hysteresis with different programmable parameters: (Search AV delay: 30-400 ms and Search Interval: 32-1024 intervals)
  9. failed Search: no intrinsic conduction is detected within the initial search period (8 cycles) or 3 out of the last 10 ventricular events are paced
  10. successful Search: if a V-sense is detected during the initial search period, hysteresis continues; each ventricular sensed event is marked as VS-Hy and AV Conduction Counter is incremented with each VS-Hy beat; when the AV Conduction Counter is ≥ 25, the device switches to AAI(R) mode with VVI back-up

10 things you need to know about RYTHMIQ (Boston Scientific)