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HeartRateVariability

This node calculates heart rate variability (HRV) from the detected R peaks in QRS complexes.

The input to this node should be the output of the RDetection node, or a packet having a marker stream named -peaks with events corresponding to the R peaks and having an instance axis where the times array holds the timestamps of those peaks. The calculated HRV statistics are based on the event markers contained within a sliding window of the defined length. The following 8 time-domain heart variability measures or statistics are calculated: - RRI (ms): R peak-to-peak interval. - SDNN (ms): the standard deviation of peak intervals - RMSSD (ms): root mean square of successive peak interval differences - SDSD (ms): standard deviation of successive peak interval differences - NN50 (#): the number of pairs of adjacent peak intervals that differ more than 50 ms - pNN50 (%): the percentage of adjacent peal interval differences that differ from each other more than 50 ms - NN20 (#): the number of pairs of adjacent peak intervals that differ more than 20 ms - pNN20 (%), the percentage of adjacent peak interval differences that differ from each other more than 20 ms. The output of this node is a new stream having the same name as the input stream except that peaks is replaced by hrv (i.e., eeg-hrv), containing a feature axis with 8 elements named as shown above. More Info... Version 1.2.0

Ports/Properties

data

Data to process.

verbose name
Data
default value
None
port type
DataPort
value type
Packet (can be None)
data direction
INOUT

window_length

Sliding window length (beats or seconds). A history of events spanning this duration (or this many events) will be used to calculate heart rate variability statistics.

verbose name
Processing Sliding Window Length
default value
300
port type
FloatPort
value type
float (can be None)

window_length_unit

Unit in which the window length is given.

verbose name
Window Length Unit
default value
seconds
port type
EnumPort
value type
str (can be None)

wait_full_buffer

Wait for the full sliding window buffer to be filled before calculating and outputting HRV statistics.

verbose name
Wait For Full Buffer
default value
False
port type
BoolPort
value type
bool (can be None)

override_axes

Replace the incoming instance axis with a time axis, add a feature axis with a single element named HRV. If False, a feature axis will not be added, and instead a field will be added to the incoming instance axis.

verbose name
Override Axes
default value
True
port type
BoolPort
value type
bool (can be None)

window_shift

verbose name
Window Shift
default value
0
port type
FloatPort
value type
float (can be None)

set_breakpoint

Set a breakpoint on this node. If this is enabled, your debugger (if one is attached) will trigger a breakpoint.

verbose name
Set Breakpoint (Debug Only)
default value
False
port type
BoolPort
value type
bool (can be None)

metadata

User-definable meta-data associated with the node. Usually reserved for technical purposes.

verbose name
Metadata
default value
{}
port type
DictPort
value type
dict (can be None)