Data Sources & Acknowledgments
Last updated: March 26, 2026
1. Real ECG Data Source
The real cardiac rhythm data presented in this Service is sourced from the PhysioNet ECG Arrhythmia Database, a large-scale 12-lead electrocardiogram database for arrhythmia study (version 1.0.0).
This database contains 45,152 patient ECG recordings with a 500 Hz sampling rate, featuring multiple common rhythms and cardiovascular conditions labeled by professional experts.
2. Citation Requirements
When referencing the real ECG data, the following citations apply:
Primary Citation
Zheng, J., Guo, H., & Chu, H. (2022). A large scale 12-lead electrocardiogram database for arrhythmia study (version 1.0.0). PhysioNet. RRID:SCR_007345. https://doi.org/10.13026/wgex-er52
Original Publication
Zheng, J., Chu, H., Struppa, D., Zhang, J., Yacoub, S.M., El-Askary, H., Chang, A., Ehwerhemuepha, L., Abudayyeh, I., Barrett, A.S., Fu, G., Yao, H., Li, D., Guo, H., & Rakovski, C. (2020). Optimal Multi-Stage Arrhythmia Classification Approach. Scientific Reports, 10.
PhysioNet Standard Citation
Goldberger, A., Amaral, L., Glass, L., Hausdorff, J., Ivanov, P. C., Mark, R., ... & Stanley, H. E. (2000). PhysioBank, PhysioToolkit, and PhysioNet: Components of a new research resource for complex physiologic signals. Circulation [Online]. 101 (23), pp. e215–e220. RRID:SCR_007345.
3. Data License
The PhysioNet ECG Arrhythmia Database is available under the Creative Commons Attribution 4.0 International Public License (CC BY 4.0). Our use of this data complies with the terms of this license.
4. Synthetic Rhythm Data
In addition to the real ECG data, the Service features synthetic (manually created) cardiac rhythms. These rhythms are designed by our team to be directionally accurate educational representations of real cardiac conditions. They are not derived from real patient data and are intended solely for educational illustration purposes.
Synthetic rhythms may differ from actual clinical ECG readings in morphology, timing, amplitude, and other characteristics. They should be used as learning aids only, not as clinical references.
5. AI-Generated Educational Content
Educational articles and learning materials on this Service were generated with the assistance of artificial intelligence (AI). These materials have been reviewed for general accuracy but may contain errors or omissions. Users should always verify information against authoritative medical textbooks, peer-reviewed sources, and qualified healthcare professionals.
6. Requesting Manipulated Data
If you require access to any manipulated or derived data based on the PhysioNet ECG Arrhythmia Database that we use in the Service, you may request this by contacting us at:
We will review such requests and provide data where feasible and permitted by the original data license.
7. Disclaimer
ShadeTree.IT LLC has made a best effort to accurately represent and present the data from PhysioNet and other sources. However, we do not guarantee the accuracy, completeness, or clinical validity of any data presented on this Service. All data is provided for educational purposes only and should not be used for clinical decision-making.
8. Contact
For questions about our data sources or to request access to derived data, please contact:
ShadeTree.IT LLC
Email: support@cardiacrhythmsim.com