ECGSim-Advanced: An Open-Source Interactive Simulator for Teaching Electrolyte, Conduction, and Repolarization Abnormalities in Electrocardiography

<ns3:p>Background Interpreting electrocardiogram (ECG) changes associated with electrolyte disturbances, atrioventricular (AV) conduction blocks, and hereditary or acquired QT syndromes is a critical skill in clinical medicine. Interactive simulation tools can greatly aid in understanding these complex ECG manifestations. We present ECGSim-Advanced, an R Shiny application designed for dynamic simulation of these specific conditions, providing a focused educational experience. Methods ECGSim-Advanced is developed in R using the Shiny framework for its interactive user interface and `ggplot2` for ECG visualization. The application mathematically generates ECG waveforms (P, QRS, T, and U waves) using Gaussian functions. Users can select simulation modes for “Normal Sinus Rhythm,” “Electrolyte Imbalance (Potassium, Calcium),” “AV Blocks (1st Degree, 2nd Degree Mobitz I &amp; II, 3rd Degree),” and “QT Syndromes (Long QT, Short QT).” Specific parameters for each condition (e.g. ST-segment/QT interval changes for calcium and QT syndromes) are modelled based on established electrocardiographic criteria. Results The application features a user-friendly interface allowing real-time manipulation of parameters such as heart rate, electrolyte levels (hypo−/hyper-kalaemia/calcaemia), AV block type, and target QTc interval. The generated ECG trace is displayed dynamically, mimicking standard ECG paper with adjustable speed and gain. On-screen callipers facilitate interval and amplitude measurements. The tool provides dynamically updated “Simulated Intervals/Info” and “Key ECG Findings &amp; Educational Notes” relevant to the selected condition. An extensive library of clinical vignettes, each with case scenarios, questions, and detailed explanations, allows users to apply their knowledge and test interpretation skills. Conclusion ECGSim-Advanced serves as an accessible, open-source educational tool for medical students, trainees, and healthcare professionals to enhance their understanding of ECG manifestations in common and critical electrolyte, conduction, and repolarization disorders. Its interactive nature, focused simulation modes, and integrated clinical vignettes promote active learning and diagnostic reasoning. Therefore, this tool can enhance ECG literacy in cardiology training programs globally.</ns3:p>