Supraventricular tachycardia (SVT) is a general term describing a group of arrhythmias whose mechanism involves the atria and atrioventricular nodal tissue for its initiation and maintenance. SVT is a common entity in clinical practice with a prevalence of 2.25 cases per 1000 in general population. Atrial fibrillation and atrial flutter are the most common presentations of SVTs. Of the remaining subtypes of SVT, atrioventricular nodal re-entrant tachycardia (AVNRT) accounts for 60% of the cases. The atrioventricular re-entrant tachycardia (AVRT) and atrial tachycardia (AT) represent approximately 30 and 10% of the cases, respectively. The mechanisms of different forms of SVT have been elucidated and are caused by either re-entrant circuit, increased automaticity or triggered activity. This chapter provides an overview of how to systematically approach a narrow complex tachycardia.
Part of the book: Interpreting Cardiac Electrograms