Supraventricular tachycardia (SVT) (SV tachycardia; thesaurus synonyms: atrial tachycardia; ectopic atrial tachycardia; nodal tachycardia; paroxysmal nodal tachycardia; paroxysmal sinuauricular tachycardia; supraventricular paroxysmal tachycardia; atrial tachycardia; ICD-10 I47. 1) is a cardiac arrhythmia that belongs to the group of conduction disorders. In the context of tachycardia, heart rates of 150-220 beats/minute occur. Tachycardia is defined by at least 3 beats with a rate of > 100/min.
Supraventricular tachycardia belongs to the group of supraventricular arrhythmias.
The origin of the excitation is in the area of the atrium of the heart (lat. Atrium cordis) at the sinus node, atrioventricular node (lat. Nodus atrioventricularis; “atrioventricular node“; AV node) or at the His bundle. These represent parts of the cardiac conduction system. In ventricular tachycardia, the origin of excitation is in the ventricular region of the heart (ventricle) in the tawara bundles.
Supraventricular tachycardia (SVT), along with ventricular tachycardia, is one of the paroxysmal (seizure-like) tachycardias.SVT is the most common symptomatic tachyarrhythmia in children, adolescents, and in patients with a congenital heart defect (vitia).Supraventricular tachycardias (SVT) include:
- AV nodal re-entrant tachycardia (AVNRT): most common paroxysmal supraventricular tachycardia (PSVT) in adults; accounts for 60-70% of all paroxysmal arrhythmias; commonly affects middle-aged women
- AV reentry tachycardia (AVRT): form of supraventricular arrhythmia that results in a circular excitation between the atrium and ventricle through an accessory pathway; most common form in children and adolescents
- Focal atrial tachycardia (originating in circumscribed atrial areas (hence the term “focal”) and are characterized by a regular atrial rhythm with a rate greater than 100 beats/min)
- Atrial flutter
On ECG (electrocardiogram), supraventricular tachycardias have a narrow ventricular complex (QRS width ≤ 120 ms) and are therefore called narrow complex tachycardias.
Forms of supraventricular tachycardia according to the localization of the arrhythmogenic substrate:
- Sinus node re-entrant tachycardia
- Atrial macro-reentry tachycardia
- Focal atrial tachycardia
- AV nodal re-entrant tachycardia (see there).
- AV re-entrant tachycardia in accessory pathway.
- Junctional ectopic tachycardia
Other forms of supraventricular tachycardia:
- Incessant – non-terminating tachycardia.
- Paroxysmal – occurring in a seizure-like manner.
- Repetitive – short sinusoidal actions between tachycardic phases.
- Sustained – persistent tachycardia lasting at least 30 seconds.
- Non-sustained – non-sustained tachycardia.
- Warming up/cooling down – frequency speeding up at the beginning and slowing down again at the end.
Sex ratio: women have a twofold increased risk of supraventricular tachycardia
Frequency peak: the disease occurs more frequently with age; people aged 65 years and older have a 5-fold increased risk compared to younger people.The prevalence (disease frequency) is 2.25/1,000 people (in Germany).
The incidence (frequency of new cases) is 35 cases per 100,000 inhabitants per year.
Course and prognosis: Affected persons perceive the tachycardia as palpitations. Typical symptoms also include vertigo (dizziness), syncope (brief loss of consciousness), dyspnea (shortness of breath) and angina pectoris (“chest tightness”; sudden pain in the region of the heart). However, there are also cases where the tachycardia remains unnoticed for hours or days. Persistent tachycardia can cause heart failure (cardiac insufficiency).
