ECG Directory

Welcome to this interactive ECG course.

Although it is one of the oldest paraclinic exams, dating back to the late 19th century, the ECG is still of crucial clinical use. This examination often still poses problems of interpretation to the medical practitioner.

This course aims to help the student, the practicing physician and even the trained cardiologist to improve his knowledge in electrocardiography. It consists of 250 traces of varying complexity with a description of each one by experts. This allows the reader to compare his analysis with that of the experts. In addition, the areas of interest of the ECG can be activated to be clearly highlighted.

We hope that these plots will be useful to readers and will improve their knowledge.

The ECGs are available sorted by keywords and categories.

ECG 006

ECG 006


Basic rhythm

Sinus rhythm, regular at 80 bpm for the first 4 beats.

P waves


PR interval

Short (< 120 ms), with a delta wave.


Enlarged (160 ms) with two distinct morphologies, sudden change of the axis between the fourth and fifth QRS complex.

ST Segment, T waves

Diffuse changes, non-specific in the terminal phase.

QT interval



Sudden change in the QRS axis. Wide QRS complexes.
Short PR interval with ∂ wave initating the QRS complex.
Negative P' wave.


Wolff-Parkinson-White syndrome (WPW) with 2 accessory pathways, one antero-septal on the right and the other infero (posterior)-septal.


The enlarged QRS complexes, combined with the short PR interval and the presence of a delta wave, are typical of WPW syndrome. The QRS axis changes depending on which of the two accessory pathways the A-V conduction uses: An antero-septal accessory pathway on the right (with significant pre-excitation) for the first four complexes, an infero (postero)-septal accessory pathway on the right for the fifth complex, a fusion complex, which is the result of simultaneous activation of the normal conduction pathways and the two accessory pathways. It is the change in the heart rate that explains the fact that the inflow uses one or the other accessory pathways.




Reading level

3 / 3