[Late effects of radiofrequency fulguration: report of five cases]

Radiofrequency fulguration is the definitive treatment of several supraventricular and ventricular arrhythmias. During radiofrequency application, the conduction in a specific zone is interrupted as a consequence of cellular necrosis and edema. The disappearance of edema, minutes or hours after the procedure, allows the reappearance of conduction and arrhythmias. On the other hand, the definitive lesion is larger than the one caused acutely, due to the progression of the scar. We report five patients, in whom there was an apparent failure of the fulguration, since at the end of the procedure there was conduction in the fulgurated zone, the tachycardia was inducible or pre excitation and arrhythmias reappeared during the follow up. All five were subjected to a new electrophysiological study and in all, fulguration had been effective. We conclude that these late effects of fulguration are due to the slow progression of fibrosis, that continues days or weeks after the procedure.