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 084

ECG 084


Basic rhythm

Sinus rhythm at 50 bpm.

P waves


PR interval

Prolonged at 300 ms.


Axis - 45 degrees. Duration: 120 ms.

T waves

Negative in V3, V4 and V5.

QT interval



rSR' aspect with rigth bundle branch blok (RBBB).
Left axis deviation.
Prolonged PR interval.


Bifascicular block with first degree A-V block (left anterior hemiblock, right bundle branch block).


With a right bundle branch block the axis remains within normal limits. The left axis deviation is due to a block on the anterior hemibranch. This bifascicular block is associated with a prolongation of the PR interval. The changes in the terminal phase cannot be interpreted in this context. The occurrence of syncope, as was the case for this patient, justifies pacemaker implantation, since there is frequently a complete A-V block.


Conduction abnormalities


Reading level

2 / 3