12Lead ECG

EKG Course

Learn EKG Analysis – Recognizing Sinus Rhythm

A useful strategy for interpreting the electrocardiogram (EKG) is the establishment of a baseline of normal EKG findings. Indeed, it is difficult to learn EKG analysis without first understanding the concept of cardiac rhythm as well as its origin and development. In this simplified EKG course, we present an example of normal rhythm that is produced by the heart’s primary “pacemaker”, which is the sinoatrial (SA) node.

Sinoatrial (SA) node

When sinoatrial depolarization precedes and leads to ventricular activation, the rhythm is called a "sinus rhythm".

Characteristics of a sinus rhythm include:

The finding of negatively deflected P waves in lead II suggests the possibility of lead misplacement, ectopic atrial activation or retrograde atrial activation from a Kent bundle or the AV node.

Any healthcare provider who wants to learn EKG interpretation is expected to recognize normal sinus rhythm. Indeed, the physiologic basis of many types of ectopic beats or arrhythmias can be understood by analyzing deviations from this rhythm. Sample EKG tracings and interactive exercises are available at Medical-ELearning.com to help both beginners and advanced users alike to master basic concepts related to the EKG and critical care.