Ventricular tachycardia (VT) (synonyms: ventricular tachycardia; tachycardia, ventricular; ICD-10 I47.2: ventricular tachycardia) is a cardiac arrhythmia that belongs to the group of conduction disorders.
VT belongs to the group of ventricular arrhythmias (arrhythmias that originate in the heart chambers (ventricles)) – they include ventricular flutter and ventricular fibrillation in addition to ventricular tachycardia.
Ventricular tachycardias (VT) are the most common cause of wide-complex tachycardia (heart rate > 120/min; QRS complex: duration ≥ 120 ms). They are considered potentially life-threatening.
Sustained ventricular tachycardia (VT) is present when it lasts longer than 30 seconds or requires a more rapid interruption for hemodynamic reasons.
Ventricular tachycardia (VT) can be divided into pulseless and pulsatile. Pulseless VT is an absolute indication for defibrillation.
Depending on the ventricular rate, three manifestations of ventricular tachycardia can be distinguished:
- Ventricular tachycardia: 100-150 beats/min.
- Ventricular flutter: 150-320 beats/min.
- Ventricular fibrillation: > 320 beats/min.
Polymorphic ventricular tachycardia as a result of a prolonged QT interval (= torsades-de-pointes tachycardia (TdP); torsades) represents a special case.
Ventricular tachycardia (VT) is further classified on the basis of its duration into non-sustained (duration up to 30 s) and sustained VT (more than 30 s).
Course and Prognosis: In most cases, ventricular tachycardia (VT) occurs as a result of structural heart disease, such as coronary artery disease (CAD; coronary artery disease) or myocardial infarction (heart attack). Rarely, VT occurs in patients without heart disease. Ventricular tachycardia is a life-threatening cardiac arrhythmia. It is an internal medicine emergency. The prognosis depends on the underlying cardiac disease. Patients who have persistent (ongoing) ventricular tachycardia in the first three months after myocardial infarction have the worst prognosis.
In this case, lethality (mortality relative to the total number of people with the disease) is as high as 85% within the first year. If persistent ventricular tachycardia is detected after myocardial infarction, those affected have a threefold increased risk of lethality compared to similar patients without these arrhythmias. Patients without heart disease do not have an increased risk of lethality compared with the normal population.
