Atrial flutter (synonyms: Atrial flutter (AFlut); Auricular flutter; ICD-10 I48.09: Atrial flutter: Unspecified) is a cardiac arrhythmia that belongs to the group of impulse formation disorders. It is the most common atrial macro-reentry tachycardia (see Causes below).
Atrial flutter belongs to the supraventricular arrhythmias (arrhythmias that originate in the atria) – in addition to atrial flutter, they include supraventricular tachycardia (SVT) and atrial fibrillation (VHF).
It can occur paroxysmally (transient, intermittent) or permanently (persistent).
On ECG (electrocardiogram), atrial flutter with regular AV conduction (usually 2:1) has a narrow ventricular complex (QRS width ≤ 120 ms) and is therefore called narrow complex tachycardia. Atrial flutter with variable AV conduction (“variable block”) represents irregular narrow complex tachycardia.
Sex ratio: males to females is 2.5: 1.
The prevalence (disease incidence) is 0.6% in those over 80 years of age.
The age-related incidence (frequency of new cases) increases from 5 cases per 100,000 population per year (< 50 years) to about 600 per 100,000 in those over 80 years of age.
Course and prognosis: Prognosis depends on the underlying disease. The most common causes of atrial flutter are organic heart disease such as coronary artery disease (CAD; affecting the coronary vessels), myocardial infarction (heart attack), and valvular disease. But atrial flutter can also occur in heart-healthy individuals. If left untreated, atrial flutter leads to palpitations in the form of tachycardia (accelerated pulse to 120-170 beats/minute). Atrial flutter is treated primarily by means of electrical cardioversion (electric shock/electric impulse to restore regular heart rhythm). Pharmacotherapy (drug therapy) of atrial flutter with antiarrhythmic drugs (drugs used to treat cardiac arrhythmias) is performed only when cardioversion is not available or as an experiment in recurrent atrial flutter. Most often, atrial flutter occurs recurrently (recurring). This can be effectively treated by radiofrequency ablation (ablation therapy; method for permanent elimination of atrial flutter using a cardiac catheter. The excitation conduction pathway leading to the arrhythmia is coagulated). Success rates for this procedure are approximately 97%.
