3D Cardiac Lead Simulator
Observe excitation inside the heart, the changing cardiac vector, its projection onto a lead axis, and the recorded ECG waveform on one synchronized timeline.
See the connection
The 3D heart and waveform cursor stay synchronized, so you can follow why the ECG looks the way it does through the vectors in between.
Switch between cutaway and exterior views. Follow excitation from the sinus node through the atria, AV node, His–Purkinje system, and ventricles, with mechanical atrial and ventricular contraction shown after electrical activation.
See local microdipoles add and cancel into M(t), then project onto lead axis L. The signed component V(t) = M(t) · L becomes the upward or downward ECG deflection.
Project the same source component onto two leads and compare the selected component with the total waveform. Follow why one event can look monophasic in one lead and biphasic in another.
View all 12 leads in the familiar 3-by-4 clinical layout with one time cursor and vertical scale. Select a waveform card to update the 3D lead axis and enlarged trace.
Switch among adult and pediatric normal ECGs and simplified examples of atrial fibrillation, bundle branch block, axis deviation, ventricular hypertrophy, and ST elevation.
Slow time to 0.05×, pause, scrub, or step by 10 ms. Manage visible structures and heart opacity from one display panel.
Use the wider overview on Mac and iPad, or keep the 3D heart, explanation, and waveform together on iPhone. The interface supports 10 major languages.
In the app
Free
Use the adult normal pattern, six representative leads (I, II, aVF, V1, V4, and V6), and fixed standard electrode positions. The core 3D, synchronized, and slow-playback learning experience is free.
ECG Vector Pro
This is not a subscription. Unlock pediatric and typical clinical patterns, all 12 and custom leads, electrode editing and misplacement, normal comparison, waveform quizzes, and favorites. Restore on devices using the same Apple Account.
Education & privacy
The app uses a simplified equivalent-dipole model of the real heart and volume conductor. It is not a medical device and must not be used for diagnosis, treatment decisions, or patient-specific waveform prediction. Clinical patterns are schematic learning examples.
No account, ads, analytics, or patient-data input. Favorites remain on your device, while Pro purchases and restoration are processed by Apple through StoreKit.