Getting started
ECG Studio computes the ECG forward from a beating heart. Activation spreads through about 37,000 tissue cells, each with its own action potential, and the twelve leads are calculated from the electrical field those cells produce. Every wave on the paper comes from the simulated tissue.
- Left: 3D electrophysiologically animated model of the heart.
- Right: a standard 12-lead layout with up to three 10-s rhythm strips, written by a sweeping cursor.
- Drag the divider to resize the two sides, or press Expand on either side.
- Mobile (landscape only): the Heart | ECG switch at the top shows one pane at a time.
- Simulation controls:
- Speed slows the whole simulation down to 1/50 of real time.
- Pause freezes the animation.
- Reset returns to normal sinus rhythm at 72 bpm with no abnormalities.
Control tabs
Clicking a tab toggles its panel. The open tab also decides what a click on the heart does.
- Rhythm: adjust the heart rate and toggle persistent arrhythmias. Click on the heart to stimulate an ectopic beat.
- Blocks: only useful during a cutaway view. Click on the conduction system to start a block.
- Ischemia: click a coronary artery to occlude it there, or (with the heart cut) click ventricular muscle on the cut face for a subendocardial patch. Use the time slider to see progression of the injury.
- Structure: add structural abnormalities with the toggles.
- Learn: a review of the key features of this ECG and common pitfalls.
About
- Anatomy: the average adult four-chamber heart of Rodero et al. (2021), built from CT scans and voxelized at 2 mm. The left ventricular free wall is thickened by about 6 mm and the heart is placed in the chest with its apex behind the 5th intercostal space.
- Electrophysiology: an event-driven cellular automaton with fibre-dependent conduction, AV-node decrement, restitution, transmural and apicobasal repolarization gradients, and a conduction system (SA node, AV node with dual pathways, His bundle, bundle branches, two left fascicles, Purkinje networks).
- ECG: limb leads blend the lead field of a computed insulated torso with Einthoven's equilateral triangle; chest leads blend the heart-vector projection with the near-field potential at each electrode.
- Calibration: parameters were tuned against textbook values for intervals, axes, voltages, bundle and fascicular blocks, hypertrophy criteria and the course of infarction. Some features are simplified or slightly exaggerated for teaching; the model is an aid to understanding, not a substitute for clinical ECGs.
- Not a medical device: ECG Studio is for education only and must not be used for diagnosis or treatment.
Created by Thomas Liou. © 2026 Thomas Liou. All rights reserved. Version 2026-10-31 (55d8d21).
Anatomy: Rodero C, Strocchi M, et al. "Virtual cohort of extreme and average four-chamber heart meshes from statistical shape model." Zenodo, 2021, doi:10.5281/zenodo.4593739. Licensed CC BY 4.0. Three.js (MIT licence) renders the heart.