# Title:
Annotated dataset of post-ischemic ventricular tachycardia electrograms (ARGO)
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# Description:
The ARGO dataset is an open-access collection of intracardiac electrophysiological recordings acquired during electroanatomical mapping procedures in patients who underwent catheter ablation for post-ischemic ventricular tachycardia (VT).
The dataset includes:
- bipolar intracardiac electrograms (EGMs)
- the corresponding unipolar EGMs
- synchronized 12-lead surface ECGs
- left ventricular electroanatomical map data
- expert annotations for EGM class
- onset/end delineation of pathological activation for abnormal EGM
The dataset contains 1962 EGMs collected from 9 patients. Each signal was independently reviewed by three expert electrophysiologists, and a final consensus annotation was then assigned.
Each bipolar EGM is labeled as:
- P: Physiological
- A: Abnormal Ventricular Potential (AVP)
- U: Unknown
For EGMs labeled as AVP, the onset and end of the abnormal ventricular potential are also provided.
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# Dataset structure:
<base>/
├── ANNOTATORS # List of annotators
├── Additional_subject_data.csv # Additional subject-level information
├── RECORDS # List of all WFDB records in the dataset
├── README.txt # Dataset structure description; this file
└── ARGODataset_Folder/
├── MATLAB_files/
│ ├── ARGODataset_MATLAB.mat # MATLAB version of the dataset packaged as a single structure
│ ├── README_MATLAB_functions.txt # Documentation for MATLAB visualization functions
│ ├── VisualizeMapsARGO_GUI.p # MATLAB GUI for electroanatomical map visualization
│ └── VisualizeRecordingsARGO.p # MATLAB function for EGM and ECG visualization
│
├── Pt1/
│ ├── AblationPoints.txt # Spatial coordinates of ablation points
│ ├── ConnectivityList.txt # Connectivity of the triangulated LV mesh
│ ├── MESHcoloring.txt # Voltage/LAT values associated with mesh vertices
│ ├── POS_POINTS.txt # Coordinates of mapped electrophysiological points
│ ├── XYZmesh.txt # X, Y, Z coordinates of LV mesh vertices
│ ├── Pxxxx.dat # Binary WFDB signal file
│ ├── Pxxxx.hea # WFDB header file containing metadata
│ ├── Pxxxx.annotation_ann1 # Annotation from expert annotator 1
│ ├── Pxxxx.annotation_ann2 # Annotation from expert annotator 2
│ ├── Pxxxx.annotation_ann3 # Annotation from expert annotator 3
│ ├── Pxxxx.annotation_consensus # Final consensus annotation
│ └── ...
│
├── Pt2/
│ └── ...
├── Pt3/
│ └── ...
├── Pt4/
│ └── ...
├── Pt5/
│ └── ...
├── Pt6/
│ └── ...
├── Pt7/
│ └── ...
├── Pt8/
│ └── ...
└── Pt9/
└── ...
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# Patient folder:
Inside ARGODataset_Folder/, each patient folder (Pt1 to Pt9) contains:
## 1. The electrophysiological data stored in WFDB (WaveForm DataBase) format for each mapped point:
- Pxxxx.dat
Binary signal file containing 15 simultaneously recorded signals:
1 bipolar EGM, 2 unipolar EGMs, and 12 surface ECG leads.
- Pxxxx.hea
Header file containing metadata for the corresponding record, including
signal gain, sampling frequency, number of samples, and channel description.
Signals were sampled at 1000 Hz and each record contains 2500 samples. Only the last beat per signal must be considered reliable. All the recordings underwent band-pass filtering by the CARTO® 3 system. Specifically, bipolar EGMs were band-pass filtered in the range 16-500 Hz, unipolar EGMs in the range 2-240 Hz, and 12-lead ECG traces between 0.5 and 120 Hz.
Pxxxx identifies a specific recording point.
## 2. Annotation files for each mapped point:
- Pxxxx.annotation_ann1
- Pxxxx.annotation_ann2
- Pxxxx.annotation_ann3
- Pxxxx.annotation_consensus
These files report:
- the class label of the bipolar EGM
- AVP onset and end, when applicable
Class labels are:
- P = Physiological
- A = AVP
- U = Unknown
For AVP signals, delineation markers are:
- ( = AVP onset
- ) = AVP end
Delineation positions are expressed as sample indices.
If a signal was not labeled as AVP by a given annotator, delineation markers are assigned to default out-of-range values set to 9999.
## 3. Electroanatomical map files:
- AblationPoints.txt
Contains the spatial coordinates of the ablation points.
- ConnectivityList.txt
Contains the connectivity information of the triangulated mesh.
- MESHcoloring.txt
Contains scalar values associated with the mesh vertices, such as
voltage and local activation time (LAT).
- POS_POINTS.txt
Contains the spatial coordinates of the mapped points associated
with the electrophysiological recordings.
- XYZmesh.txt
Contains the X, Y, Z coordinates of the mesh vertices.
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# Data summary:
Number of patients: 9
Total number of EGMs: 1962
Consensus class distribution:
- Physiological: 776
- AVP: 940
- Unknown: 246
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# Usage notes:
Electrophysiological data from the CARTO® 3 system were converted into
WFDB-compatible files, validated using WFDB tools, and are fully compatible
with analysis functions (e.g., rdsamp, rdann) from the WFDB Software Package.
To get started, users can load any record and its annotations using standard
WFDB or MATLAB commands, as shown in the following MATLAB example:
% Read the signals, sample frequency, and the sampling intervals:
[signal, Fs, tm] = rdsamp('ARGODataset_Folder/Pt1/P71')
% Read the annotations:
[ann, anntype, ~, ~, ~, comments] = rdann('ARGODataset_Folder/Pt1/P71','annotation_consensus')
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# If you use this dataset, please cite the associated data descriptor paper:
Orrù M, Baldazzi G, Zirolia D, Bertagnolli L, Viola G, Solinas MG, Pani D. (2026) The ARGO dataset: annotated and delineated intracardiac electrograms of post-ischemic ventricular tachycardia. PLOS ONE 21(6): e0350993. https://doi.org/10.1371/journal.pone.0350993
# Contact:
Giulia Baldazzi
Department of Electrical and Electronic Engineering
University of Cagliari, Italy
Email: giulia.baldazzi@unica.it