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 007

ECG 007


Basic rhythm

Regular narrow complex tachycardia at 125 bpm.

P waves

Positive in I, II, negative in III and aVF.

PR interval



Normal axis, micropotentiels in peripheral leads.

ST segment


T waves


QT interval



Negatives P' waves in II,III and aVF. RP' > P'R.
Micropotentiels of the QRS complexes.


Low right atrial tachycardia. Micropotentiels in the QRS complex.


The origin of the tachycardia can be localised in the lower part of the right atrium due to the caudo-cranial direction of the P' wave. Here, this is a case of atrial tachycardia (and not of atypical atrioventricular nodal re-entrant tachycardia or permanent junctional reciprocating tachycardia (PJRT/Coumel's tachycardia). It is the RP' > P'R ratio that allows this diagnosis to be made.


Narrow QRS complex tachycardia


Reading level

2 / 3