The ECG Lab
Three hands-on tools for the surface ECG. See how one heartbeat paints all twelve leads, compare the rhythms side by side, and walk a tracing through a systematic read. The companion to Volume XI, Reading the ECG.
The 12-Lead Vector Explorer
Every lead records the same heartbeat from a different angle. A lead's deflection is just the projection of the heart's mean electrical vector onto that lead's axis: pointing at the lead gives a tall upright R, pointing away gives a deep S, and perpendicular gives a flat, isoelectric complex. Drag the arrow and watch all six leads redraw.
The Rhythm Atlas
The rhythms you meet on a monitor, each with a sweeping trace. Compare the ones that look alike: Mobitz I versus Mobitz II, monomorphic VT versus the twisting axis of Torsades, a paced beat versus a native one.
Baseline
Supraventricular
AV block
Ventricular
Inherited pattern
The Systematic Read
A tracing is safe to read when you always read it the same way. Step through the five questions and watch each one light up the part of the beat it asks about.