ECG Vector

ECG Vector is an educational simulator for exploring how electrical activity in the heart relates to ECG waveforms. Switch between six learning workspaces on Mac, iPhone, and iPad.

ECG Mechanism
Observe 3D activation and repolarization, the cardiac source vector, and lead-axis projections in sync with the ECG. Use single-lead decomposition, two-lead comparison, and the 12-lead view to understand differences in polarity and shape.

Ion & ECG
Explore educational approximations linking Na⁺, K⁺, Ca²⁺, H⁺ (pH), and major ion currents to action potentials, ECG measures, and clinical conditions. See differences from the reference alongside explanations.

Ventricular Action Potential
Numerically simulate a single ventricular cell using Luo–Rudy I (1991). View membrane voltage, Na⁺/Ca²⁺/K⁺ currents, conductances, and gates together. Pause at the peak sodium current and compare with the membrane diagram.

Cardiac Rhythm
View representative regional action potentials on a shared timeline. Adjust the sinus cycle, conduction speed, and AV delay, and explore schematic examples of normal rhythm, bradycardia, tachycardia, and AV block.

ECG & Conditions
Compare normal and representative clinical patterns in single-lead or 12-lead views, with explanations of waveform features and their mechanisms.

Learn & Quiz
Identify patterns from the 12 leads and rhythm strip, then deepen your understanding with explanations.

Free access includes Adult Normal and Right Bundle Branch Block, all standard 12 leads, fixed electrode placement, four guided Ion & ECG examples, and comparison and quiz samples. The standard ventricular-cell model, stimulus adjustment, playback, current and gate inspection, and all Cardiac Rhythm features are also free.

The one-time ECG Vector Pro purchase unlocks unrestricted Ion & ECG adjustment and its synchronized 12-lead response; ventricular-cell conductance adjustment, suppression presets, and comparison with the standard trace; additional pediatric and clinical patterns; custom leads; electrode editing; and the complete comparison and quiz libraries. This is not a subscription.

For education only—not diagnosis, treatment decisions, or patient-specific prediction. Ion & ECG uses educational response approximations; the ventricular-cell model is based on guinea-pig ventricular muscle; Cardiac Rhythm uses waveform templates and activation timings. A single-cell membrane potential is not a surface ECG or a QT interval. No sign-in or external hardware is required.