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 020

ECG 020


Basic rhythm

Regular sinus rhythm at 70 bpm.

P waves

Regular, blocked every two.

PR interval

Normal for the conducted P waves.


Normal duration.

ST segment


T waves

Morphology not interpretable on a single lead.

QT interval

Prolonged (560 ms).


Blocked P wave.
Prolonged QT interval.


Congenital long QT syndrome. Second degree A-V block, Mobitz type II with 2:1 conduction.


Congenital long QT syndrome is a congenital, idiopathic and rare condition. Usually prolongation of the QT interval occurs in the context of various cardiac, metabolic or endocrine conditions, or as a side-effect of antiarrhythmic drug treatment (amiodarone, quinidine). It is important to diagnose congenital long QT syndrome because the risk of sudden death exists. Repolarisation disturbances prolong the refractory phase of the ventricles. In the present case, the refractory period is maintained beyond the moment when the next atrial depolarisation occurs, which is therefore blocked. The A-V block is therefore not due to organic lesions in the conduction pathways, but rather it is of functional origin.


Conduction abnormalities


Reading level

3 / 3