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 068

ECG 068


Basic rhythm

Sinus rhythm at 68 bpm.

P waves


PR interval



Normal axis, duration and morphology. Sudden transition at V4 in the precordial leads.

Segment ST

Oblique, ascending elevation at V3.

T waves

Negative from V1 to V3, and with very sharp points from V4 to  V6. At V3 there is always a marked oblique angle in the descending part.

QT interval



ST segment modifications.


Previous sub-epicardial ischaemia due to a 90% stenosis of the left anterior descending artery.


The image at V3 (oblique and ascending elevation of the ST segment and marked oblique angle in the descending part of the T wave which finally becomes negative) indicates a critical stenosis (90% in this patient) of the left anterior descending artery. This is an urgent coronary case requiring revascularisation as soon as possible.


Ischemia and myocardial infarction


Reading level

1 / 3