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 008

ECG 008


Basic rhythm

Regular narrow complex tachycardia at 147 bpm.

P waves

Not clearly visible.

PR interval

Not visible.


Normal axis and morphology. Small negative rounded deflection (P' wave) in the terminal portion of the QRS complex in the inferior leads.

ST segment, T waves

Non-specific changes in the terminal phase.

QT interval



Negatives P' waves in II, III and aVF at the end of the QRS complexes.
Narrow QRS complexes tachycardia.


Typical atrioventricular nodal re-entrant tachycardia.


The P' wave is most often not visible in typical atrioventricular nodal re-entrant tachycardia, as it is concealed in the QRS complex. Sometimes it appears at the end of the QRS complex (as is the case here in the inferior leads), or in the initial portion.


Narrow QRS complex tachycardia


Reading level

2 / 3