Electrode to ECG Simulator - Lead Reversal, Artifact and Filters

Every ECG is a set of projections of one moving vector, recorded through cables that can be crossed, electrodes that can be misplaced, and filters that quietly reshape what reaches the paper. This simulator makes all three visible at once.

Change something on the left and the twelve leads redraw immediately. The vectorcardiographic loops sit alongside, so it stays clear that the leads are views of a single underlying signal rather than twelve independent recordings.

Using it in a teaching session

Lead reversal is the obvious place to start. Cross the arm cables without saying so and ask the room what is wrong. Most will reach for dextrocardia, and the discussion about how to tell the two apart is the lesson.

Filters are the part people never see taught. Set a high-pass filter too aggressively and watch the ST segment distort. Anyone who has argued about ST elevation on a monitor strip will recognise what they are looking at.

Artifact is the third theme. Add muscle noise or mains hum to a single electrode and follow which leads it reaches, because the distribution is the clue to which electrode is at fault.

Quiz mode hides a fault and asks the user to name it from the strip alone.

Real tracings

A 12-lead CSV can be loaded in place of the synthetic signal, so a recording from your own department can be examined with the same tools.

What the model simplifies

The underlying signal is synthetic and cleaner than any real recording, and the torso is treated as a uniform volume conductor. It shows the logic of how placement, cabling and filtering shape the tracing, not the individual variability you meet on a ward.