Cardiology Menu

The Heart

Symptoms of Heart Disease

Diagnosing Heart Disease

Introduction to the ECG

Rhythms and Arrhythmia

Rhythms and Arrhythmia

The Sinus Node

• Sinus Rhythm

• Sinus Tachycardia

• Sinus Bradycardia

• Sinus Node Disease

The Atria

• Atrial Ectopic Beats

• Atrial Fibrillation

• Atrial Flutter

• Supraventricular Tachycardia

The Atrioventricular Node

• First Degree Block

• Second Degree Block

• Third Degree Block

• Bundle Branch Block

The Ventricles

• Ventricular Ectopic Beats

• Ventricular Tachycardia

• Ventricular Preexcitation

• Myocardial Ischaemia

Rhythms and Arrhythmia

Atrial Flutter

Atrial flutter refers to rapid and regular contractions (usually in the range of 120 to 350 times each minute) that is characterised on the ECG by a saw-tooth appearance.

Not all atrial contractions are necessarily conducted to the ventricles due to a variable block within the atrioventricular node. When conduction to the ventricles does occur, the QRS complex morphology is regular but RR intervals may be random or follow a specific pattern.

The ECG trace below shows regular flutter waves (arrowed) at a rate of five per second. Ventricular conduction is occurring after every two (shaded RR intervals) or three (unshaded RR intervals) atrial contractions.