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 113

ECG 113


Basic rhythm

Irregularly irregular; around 150 bpm.

P waves


PR interval



Prolonged (120 ms), R wave in V1 only, rsR pattern in V2, pronounced S wave in I (and V6). Axis: + 110°.

T waves

Widespread and non-specific changes in the repolarisation.

QT interval



Irregularly irregular narrow QRS complexes tachycardia.
Right axis deviation.


Rapid atrial fibrillation, right bundle branch block (RBBB), right axis deviation.


The QRS pattern in V1, V2 (as well as in I and V6) is typical of right bundle branch block, with a right axis deviation suggesting a right ventricular hypertrophy. The combination of atrial fibrillation, right bundle branch block and right axis deviation must systematically suggest mitral stenosis or pulmonary hypertension due to other causes.


Narrow QRS complex tachycardia


Reading level

3 / 3