[Multiple pathway tachycardias: electrophysiological properties and fulguration of accessory pathways in 2 cases]

We report two patients (male, 35 and female, 28 years old) with recurrent and refractory tachycardias referred for an electrophysiological study. EKG showed left lateral accessory pathway in both, two tachycardias with identical morphology but with different frequency and activation sequence were detected. One was orthodromic with anterograde conduction by the His-Purkinje budle and retrograde by the accessory pathway and the other with slow nodal anterograde conduction. The accessory pathway was first fulgurated with radiofrequency at the third attempt. Posteriorly, a nodal reentry tachycardia was induced in the first patient and in the second, a double nodal pathway was confirmed. In both, the slow pathway was modified using Jackman's technique, after three and four attempts respectively. After these applications, the induction of tachycardia with programmed atrial or ventricular stimulation, with or without isoproterenol, was not possible. It is concluded that radiofrequency fulguration is a reasonable therapeutic alternative for patients with multiple circuit tachycardias.