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 063

ECG 063


Basic rhythm

Sinus rhythm, regular at 66 bpm.

P waves


PR interval

Decreased (120 ms).


Q wave in III (q in II and aVF). R wave in V1.

ST segment


T waves


QT interval



∂ wave and short PR interval.
Negative ∂ wave.


Wolff-Parkinson-White syndrome with a left inferior (posterior) bundle.


A shortening of the PR interval primarily suggests Wolff-Parkinson-White syndrome. The initial negative deflexion in the inferior leads should not be interpreted as a Q wave related to necrosis. It corresponds to a delta wave, which is only slightly visible but positive in V1. The polarity of the delta wave allows us to locate the site of the accessory pathway to a left inferior position.




Reading level

1 / 3