[Radiofrequency ablation of right accessory pathways]

Accessory pathways are muscular connections between auricles and ventricles, present in different points of mitral and tricuspid annuluses. These pathways participate in 50% of paroxysmal supraventricular tachycardias and the definitive cure of the arrhythmia is their ablation.

To report our experience in patients with right accessory pathways.

Fifty consecutive patients treated between 1990 and 1996 are reported. Eight had a history of syncope, two had a diagnosis of Ebstein disease and 36 had a pre-excitation in the surface electrocardiogram.

Fifty four accessory pathways were identified, since four patients had two pathways. Twenty four pathways were posteroseptal, 15 were lateral, 9 were medioseptal and 6 were anteroseptal. One patient had also a nodal reentry tachycardia. Fulguration was attempted in 39 patients and it was finally successful in 32. Three patients required more than one session. There were six relapses and all were successfully ablated in a second session. A mean of 28 radiofrequency applications were done (range 1-76), mean laboratory time was 6 hours and mean radioscopy time was 70 min. Four patients had a transient atrioventricular conduction blockade.

Radiofrequency ablation of accessory pathways has a high degree of success and a low rate of complications.