This EKG quick reference provides a summary and a sample tracing for over forty conditions. This list can be filtered by rhythm category. Free online lessons. Free medical terminology flash cards. Toggle Menu Practical Clinical Skills. Arrhythmia Guide.
The rhythm is either sinus rhythm or not sinus rhythm. Sinus rhythm refers to the origination of the electrical activity coming from the sinus node — also known as the sinoatrial node, or SA node. The first ECG strip below shows a P wave with sinus morphology, thus normal sinus rhythm. If the P wave has a morphology different from the typical sinus morphology, it is termed ectopic, meaning coming from somewhere other than the sinus node.
Patient Information Handout. Sick sinus syndrome comprises a variety of conditions involving sinus node dysfunction and commonly affects elderly persons. While the syndrome can have many causes, it usually is idiopathic. Patients may experience syncope, pre-syncope, palpitations, or dizziness; however, they often are asymptomatic or have subtle or nonspecific symptoms.
There are two different rates that can be determined on an ECG. The atrial rate is indicated by the frequency of the P waves. The ventricular rate is indicated by the frequency of the QRS complexes. In the absence of disease, the atrial rate should be the same as the ventricular rate.