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 067

ECG 067


Basic rhythm

Sinus rhythm, regular at 75 bpm.

P waves

Negative in I.

PR interval



Axis +110°, normal morphology and duration.

ST segment


T waves

Negative in I.

QT interval



Negative P wave, QRS complex and T wave.


Inversion of two peripheral electrodes (left arm and right arm).


In I and aVL, the trace is the opposite of a normal trace (the P, QRS and T waves are all inverted), due to the inversion of the electrodes on the upper limbs. This inversion means that lead II takes the place of lead III (and vice versa), which explains the (false) right axis deviation. The precordial leads are not affected by the inversion, distinguishing this trace from a trace showing dextrocardia.


Various cardiopathy


Reading level

1 / 3