INSTRUCTIONS ON USING SEMIA, Version 3.0.1
Semia, version 3.0.1, is a tool to view time series of diagnostic and morphology
parameters of long-term ambulatory recordings, and ST segment annotations with
their corresponding ECG waveforms of the Long-Term ST Database.
To run Semia type following command:
semia &
To successfully run Semia following files are needed in the current working
directory:
sXYYYZ.hea - Header file, where X is the number of ECG leads, YYY is the
patient number, and Z is the record number of this patient.
This file also contains comments of human annotators, diagnostic
data of the patient, and technical data of the record.
sXYYYZ.dat - Signal file (ECG data) of the record
sXYYYZ_fin.dmy - File with time series of "fine" diagnostic and morphology
parameters obtained on average heart beats
sXYYYZ_raw.dmy - File with time series of "raw" (resampled - 0.5 samples/sec -
and smoothed - 7 point - time series) diagnostic and morphology
parameters
sXYYYZ_1.sta - ST annotation markers according to annotation protocol A
sXYYYZ.cnt - File containing numbers of annotated ST events and their
durations according to annotation protocols A, B, and C and
numbers of normal and abnormal heart beats
semia.opt - File containing Semia's options
semia.hlp - File containing this text
MAIN WINDOW:
After running Semia, main window appears with following buttons:
<Open> - Open record (dialog to open a record appears)
<Quit> - Exit Semia (dialog to exit Semia)
<Lead0> - Open "Lead0" window
<Lead1> - Open "Lead1" window
<Lead2> - Open "Lead2" window
<Data> - Open "Data" window
<KLCoeff> - Open "KL" window
<DiagData> - Open window with annotators' comments, diagnostic data of the
patient and technical data of the record
<N_Events> - Open window with numbers of annotated ST events and their durations
according to annotation protocol A, and with numbers of normal and
abnormal heart beats
<AplOp> - Apply semia's options (reads the semia.opt file)
<Help> - Open window with this text
The "Lead" windows display ST annotations and time series of diagnostic parameters
(raw and fine ST level functions, raw and fine ST slope functions, raw linearly
interpolated ST reference function, raw ST deviation functions, raw and fine heart
rate functions, and annotated ST episodes).
The "Data" window displays ECG signals corresponding to time instance of active
reference annotation (upper) and ECG signals corresponding to time instance of
marker (lower).
The "KL" window displays time series of ST segment and QRS complex Karhunen-Loeve
Transform morphology coefficients.
DIALOG TO OPEN AND LOAD A RECORD:
When typing the record name in the dialog to open a record, end it with <CR>. It
is necessary to end the record name with <CR>.
HINT:
A useful hint on how to examine and view ST segment episode annotations with their
corresponding ECG waveforms is at the bottom of this help text.
OPTIONS:
If modifying Semia's options, edit semia.opt file. Rows in the file have following
meaning:
LineWidth:1 Set the width of the functions
Color1:green Color of global and local reference
Color2:blue Color of active annotation
Color3:red Color of marker and overlays within windows
Color4:red Color of overlay from the lead 0
Color5:red Color of overlay from the lead 1
Color6:red Color of overlay from the lead 2
Line width could be 1,2,3,4, while colors could
be colors "by name". No white spaces.
"LEAD0", "LEAD1", AND "LEAD2" WINDOWS:
What are fine and raw time series or functions? Fine functions are those obtained
on average heart beats after noise detection during preprocessing phase. Raw
functions are those after resampling and smoothing of fine functions. Sampling
frequency is 0.5 samples/sec.
Semia works in three different modes. You change modes using buttons "Subtr"
("UnSubtr"), and "ConsLR" ("ConsGR"):
- Subtracted mode ("Subtr"), active reference is global reference ("ConsGR"):
Upper part of a "Lead" window displays ST deviation (subtracted ST
level) function
- Unsubtracted mode ("UnSubtr"), active reference is global reference ("ConsGR"):
Upper part of a "Lead" window displays ST level (unsubtracted ST
level) function
- Unsubtracted mode ("UnSubtr"), active reference is local reference ("ConsLR"):
Upper part of a "Lead" window displays ST level (unsubtracted ST
level) function
In the bottom part of the "Lead" windows, raw and fine time indexes are indicated
by short vertical lines (upper - raw indexes, lower - fine indexes).
Description of buttons and menus in the "Lead" windows:
< < > - Move backward for one half of screen
< << > - Move backward for one screen
< > > - Move forward for one half of screen
< >> > - Move forward for one screen.
Moves are made synchronous for all three (or two) leads.
<Marker> - Set marker. After clicking "Marker" button, click into the "Lead" window.
Vertical marker appears in the "Lead" and "KL" windows.
<Subtr>/(<UnSubtr>) - Entering subtracted (or unsubtracted) mode. As a result,
subtracted ST level function, i.e., ST deviation function
(or unsubtracted ST level function, i.e., ST level
function) is displayed in the upper part of "Lead" window.
<OvrApp>/(<UnOvAp>) - Overlay (unoverlay) linearly interpolated ST reference
function onto ST level function in the upper part of "Lead"
window
Menu <OvrLds> - Overlay ST level functions from other leads.
Options:
<Lead0> - Overlay ST level function from lead 0
<Lead1> - Overlay ST level function from lead 1
<Lead2> - Overlay ST level function from lead 2
<UnOvrly> - Unoverlay overlaied functions.
Menu <HRate> - Displays raw and fine ST level functions, raw and fine ST slope
functions, raw ST deviation functions, raw and fine heart rate
functions, and annotated ST episodes.
Options:
<HRate> - Raw ST level (deviation) function (above), fine
heart rate (below)
<HR Raw> - Raw ST level (deviation) function (above), raw
heart rate (below)
<ST Fine> - Raw ST level (deviation) function (above), fine ST
level function (below)
<STsl Fine> - Raw ST level (deviation) function (above), fine ST
slope (below)
<STsl Raw> - Raw ST level (deviation) function (above), raw ST
slope (below)
<Episodes> - Raw ST level (deviation) function (above),
annotated ST episodes (below)
<Hide HR> - Raw ST level (deviation) function (above),
none (below).
Menu <12 min> - Time scale (from 1 minute to 96 hours).
Options:
<1 min>, <2 min>, <3 min>, <6 min>, <9 min>, <12 min>,
<24 min>, <30 min>, <1 h>, <2 h>, <4 h>, <6 h>,
<12 h>, <24 h>, <48 h>, <96 h>.
Chosen scale corresponds to one screen.
Menu <100 uV> - Amplitude scale (from 20uV to 5 mV).
Options:
<20 uV>, <25 uV>, <50 uV>, <75 uV>, <100 uV>, <125 uV>,
<150 uV>, <200 uV>, <250 uV>, <500 uV>, <750 uV>, <1 mV>,
<2 mV>, <5 mV>.
Chosen scale corresponds to one unit (0 - 1).
<Exm> - Examine annotation. After clicking "Exm" button, click as close as
possible to an annotation to be examined. Examined annotation becomes
current active annotation.
<ConsLR>/(<ConsGR>) - Currently examined local reference becomes active reference
(global reference becomes active reference). In the case
that a local references is active, examining any other
local reference makes this last local reference as active
reference.
Description of annotation markers:
M (Marker) - This is not an annotation
GR - Global reference
LR - Local reference
BI - Beginning of ischemic ST episode
XI - Extrema of ischemic ST episode
EI - End of ischemic ST episode
BR - Beginning of heart-rate related ST episode
XR - Extrema of heart-rate related ST episode
ER - End of heart-rate related ST episode
NO - Noise
UB - Beginning of unreadable interval
UE - End of unreadable interval
Description of the left side of the "Lead" window. From top to bottom:
[units][uV] R: - Description of units, record number and lead
Mode - MANUAL MODE
Mode - UNSUBTRACTED/SUBTRACTED
ACTIVE: - Active reference (global or local reference)
RAW: - Raw time of marker [hh:mm:ss.tht]
HRate: - Raw heart rate [bpm]
ST80: - Value of raw ST level function [uV] at marker / value of raw ST level
function [uV] at current active annotation
STSb: - Value of raw ST deviation function [uV] at marker / value of raw ST
deviation function [uV] at current active annotation
FINE: - Fine time of marker [hh:mm:ss.ttt]
HRate: - Fine heart rate [bpm]
ST80: - Value of fine ST level function [uV] at marker / value of fine ST level
function [uV] at current active annotation
Description of the function shown in the lower part of the window
[time]
There exists a "fast mode" for setting marker and examining annotations:
- Any click into a "Lead" window (upper two thirds) using left mouse button
inserts a marker. Vertical marker appears in the "Lead" and "KL" windows.
- Any click in a "Lead" window close to an annotation using middle mouse button
examines this annotation. Examined annotation becomes current active
annotation.
Any click into lower third of a "Lead" window displays values of the functions
at this time instance in the left side of the "Lead" window. Left column of this
area displays the values of the functions at the position of the last click, while
the right column in this area displays the differences of values of the functions
for the last two clicks.
"DATA" WINDOW:
Lower edge of the "Data" window is resizable.
Menu <Lead 0> - Signals of lead to display at time instances of active reference
and marker.
Options:
<Lead 0> - Display lead 0
<Lead 1> - Display lead 1
<Lead 2> - Display lead 2.
Menu <OvrLds> - Signals of lead to overlay.
Options:
<Lead 0> - Overlay lead 0
<Lead 1> - Overlay lead 1
<Lead 2> - Overlay lead 2
<UnOvrly> - Unoverlay overlaied leads.
Menu <16 sec> - Time interval surrounding raw index of active reference, or
marker, from which individual heart beats are taken to compute
average heart beat (from single to 5 min).
Options:
<Sngl>, <2 s>, <4 s>, <6 s>, <10 s>, <16 s>, <20 s>,
<30 s>, <1 min>, <2 min>, <3 min>, <4 min>, <5 min>.
Menu <520 ms> - Width of the average heart beat (from 200 ms to 1000 ms)
Menu <Ovrly> - How overlays are plotted.
Options:
<Ovrly> - If overlays are used in menu <OvrLds>, this option
yields in overlays
<OvShift> - If overlays are used in menu <OvrLds>, this option
yields in overlays with shifts.
Menu <6s> - Time scale (from 1 sec to 60 sec).
Options:
<1 s>, <2 s>, <4 s>, <5 s>, <6 s>, <8 s>, <10 s>, <12 s>,
<15 s>, <20 s>, <25 s>, <30 s>, <45 s>, <60 s>.
Chosen scale corresponds to one screen.
Menu <1 mV> - Amplitude scale (from 50 uV to 5 mV).
Options:
<50 uV>, <75 uV>, <100 uV>, <125 uV>, <150 uV>, <200 uV>,
<250 uV>, <500 uV>, <750 uV>, <1 mV>, <2 mV>, <5 mV>.
Chosen scale corresponds to one unit (0 - 1).
<OvrRef> - Overlay reference waveform over the marker's waveform
Description of the left side of the "Data" window. From top to bottom:
[units][uV] R: - Description of units and record number
Mode - FINE MODE
HRate: - Fine heart rate [bpm]
Mean: - Samples used to compute amplitudes in ECG signals [smp]
ABeat: - Window to compute average beat [sec]
Refer. - Time (fine) of the active reference
Marker - Time (fine) of the marker
Time tick: [msec]
"KL" WINDOW:
Menu <ST KL> - Display ST segment or QRS complex Karhunen-Loeve Transform
coefficients.
Options:
<ST KL> - Display ST segment KLT coefficients
<QRS KL> - Display ST segment KLT coefficients.
<DistF> (<UnDistF>) - Overlay ST segment or QRS complex distance function, i.e.,
Mahalanobis distance function, (unoverlay ST segment or QRS
distance function). The distance function is computed using the
first five ST segment or QRS complex KLT coefficients.
Menu <1 std> - Amplitude scale (from 0.1 std to 20 std).
Options:
<0.1 std>, <0.125 std>, <0.2 std>, <0.25 std>, <0.5 std>, <1 std>,
<2 std>, <4 std>, <5 std>, <8 std>, <10 std>, <20 std>.
Chosen scale corresponds to one unit (0 - 1).
Any click into the "KL" window displays values of KL coefficients (and value of
distance function, if option "Ovrly" is used).
HINT:
A useful hint on how to examine and view ST segment episode annotations with their
corresponding ECG waveforms:
1. Open and load a record.
2. Open a "Lead0", "Lead1", or "Lead2" window in which you wish to examine the ST
segment episode annotations.
- Click the "OvrApp" button to get ST reference function.
- Choose proper time scale in the "12 min" menu.
- Display annotated ST segment episodes by choosing the "Episodes" option in
the "HRate" menu.
- Find an ST segment episode of interest by moving forward/backward.
3. Open the "Data" window.
- Choose the ECG lead (that to be displayed) in the "Lead 0" menu.
- Choose the "1 s" option in the "6 s" (Display:) menu.
- Choose, say, the "100 uV" or "200 uV" option in the "1m V" (Display:) menu.
4. In previously chosen "Lead" window, examine closest local reference (LR) at the
left side of the ST segment episode of interest. For examining, you can use
"Exm" button, or, simply move the cursor in the close neighborhod of the local
reference of interest and click using middle mouse button. Average heart beat
(from 16 second window) corresponding to the local reference annotation will
appear in the lower part of the "Data" window.
5. Click the "ConsLR" button in the "Lead" window to make currently examined local
reference active. The average heart beat corresponding to examined local refe-
rence annotation will be copied to the upper part of the "Data" window.
6. Examine the extrema (XI: ischemic ST episode, XR: heart-rate related ST episo-
de) of the ST segment episode of interest. The corresponding average heart beat
will be displayed in the lower part of the "Data" window.
7. Click the "OvrRef" button in the "Data" window to overlay the average waveform
of the local reference down and over the average waveform of the episode extre-
ma in the lower part of the "Data" window.