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 041

ECG 041


Basic rhythm

Narrow complex tachycardia at 110 bpm.

P waves

Negative in I and aVL, positive with large amplitudes in the inferior leads, detached from the QRS complex.

PR interval

RP' > P'R.


Axis, morphology normal.

ST segment


T waves


QT interval



P' wave with RP' > P'R.
Negative P' wave in I and aVL.


Left atrial tachycardia


The diagnosis of left atrial tachycardia is supported for two reasons: the polarity of the P' wave (negative in I, aVL, positive in V1), which creates an ectopic P' wave at the origin of the left atrium, and the RP'> P'R interval.


Narrow QRS complex tachycardia


Reading level

2 / 3