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 053

ECG 053


Basic rhythm

Narrow complex tachycardia, regular at 120 bpm.

P waves

Replaced by regular baseline oscillation that is clearly visible in the inferior leads, rate of 260/min.

PR interval

Not definable.


Axis at –30°, microvoltage in the peripheral leads, low voltages in the precordial leads; normal duration.

ST segment


T waves


QT interval



F waves in sawtooth.


Typical atrial flutter with clockwise rotation (inverted) and 2:1 A-V conduction. Micropotentiels.


The "sawtooth" or "factory roof" pattern of the baseline suggests atrial flutter. The diagnosis of typical atrial flutter with clockwise rotation, therefore inverted, was confirmed by endocavitary investigation. Two to one A-V conduction is the most frequently observed.


Narrow QRS complex tachycardia


Reading level

1 / 3