Tachycardia induced tachycardia: case report of right ventricular outflow tract tachycardia and AV nodal reentrant tachycardia

Tachycardia induced tachycardia, or so called double tachycardia, is rare. A 34 year old woman is described who had a history of syncope, frequent ext rasystoles, and episodes of non-sustained ventricular tachycardia, perceive d as palpitation, without syncope. At electrophysiological study, during in fusion of isoprenaline, an episode of non-sustained ventricular tachycardia arising from the right ventricular outflow tract initiated sustained atrio ventricular nodal reentrant tachycardia, thought to be the cause of the pat ient's syncope. Ablation of the right ventricular outflow tract focus aboli shed the ventricular ectopy; the slow AV nodal pathway was also ablated. Th e patient no longer has either syncope or palpitation.