The QRS complex consists of the Q wave, the R wave and the S wave. The QRS complex comes after the P wave when the SA nodal action potential travels through the AV node to the ventricles to cause ...

A 76-year-old woman presents with a persistently rapid heart rate that she attributes to her pacemaker. What does the ECG show?

Because the electrical activation originates at or near the AV node, the P wave is frequently not seen; it can be buried within the QRS complex, slightly before the QRS complex or slightly after ...

The regular arrhythmia occurring at the beginning of the electrocardiogram was identified as ventricular bigeminy. Single ventricular premature complexes (VPCs), as well as pairs and triplets of ...