User Manual Part 3

7-14
PATIENT D IAGNOSTICS
ARRHYTHMIA LOGBOOK
The HRV monitor screen displays a set of measurements and a HRV plot
based on the most recent 24-hour collection period in the Last Measured
portion of the screen; measurements from a previously saved collection period
are displayed in the Reference portion of the screen. Both collection periods
can be viewed simultaneously to compare data that could show trends in the
patient’s HRV c hanges over a period of time. By saving the Last Measured
values to the Reference portion of the screen, you can view the last measured
data during a lat er session.
HRV Collection Criteria
The pulse generator only collects interval data for HRV when the Normal
Brady/CRT mode is programmed to non-rate-responsive tracking modes (VDD
or DDD). In addition, only valid sinus rhythm intervals are used in the HRV data
calculation s. For HRV, valid intervals are th ose which include only valid HRV
events. HRV event validation criteria are listed below:
Valid HRV Events Invalid HRV Events
AS with an interval not faster
than MTR, followed b y a VS
AP
AS followed by VP at the programmed
AV Delay
AS with an interv a l faster than MTR
Non-tracked VP events
Consecutive AS events (no
intervening V event)
VP-Ns
Rate Smoothing events (e.g., RVP↑)
PVC
HRV data may not be reported for a variety of reasons; the most common
are as follows:
• Brady mode is not DDD or VDD
• Less than 67% of the 24-hour collection period (approximately 16 hours)
contains valid HRV event s
• Brady Parameters were programmed within the last 24 hours
- DRAFT -