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 032

ECG 032


Basic rhythm

Regular at 50 bpm.

P waves

Not visible.

PR interval

Not definable. At irregular intervals, spikes are present (stimulation artefacts).


Enlarged (200 ms). Axis -10°.

ST segment, T waves

Diffuse and non-specific changes in the terminal phase.

QT interval



Isolated spike.
Idioventricular rhythm.


Accelerated idioventricular rhythm (AIVR). VVI pacemaker malfunction.


The trace, consisting of enlarged QRS complexes with a low heart rate that are not preceded by a P wave, is that of an AIVR, independent of a pacemaker that has malfunctioned. There is no relation between the spikes and the QRS complexes. The irregularity of the spikes shows that the pacemaker has partially preserved its sensing function. It is not a case of the battery running out but rather of the ventricular sensor malfunctioning.




Reading level

2 / 3