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 136

ECG 136


Basic rhythm

Sinus rhythm at 60 bpm; irregular ventricular rhythm.

P waves


PR interval

Prolonged with non-conducted P waves.



QT interval



P wave with prolonged PR interval.
Blocked P wave.


Second degree A-V block, Wenckebach type.


This is trace is typical of Mobitz type I second degree A-V block. The relationship between the P waves and the QRS complexes is not clear, but it is the irregularity of the ventricular rhythm that confirms that some P waves are conducted. The conduction disturbance definitely originates in the A-V node since the QRS complex is narrow.


Conduction abnormalities


Reading level

2 / 3