Radiofrequency catheter ablation of accessory pathways: the initial experience in Singapore

Radiofrequency catheter ablation is a recently introduced non-surgical technique for curing patients with arrhythmias as a result of conduction over an accessory pathway in patients with the Wolff-Parkinson-White (WPW) syndrome. We present our initial experience with this technique. There were 90 patients (61 males, 29 females) with a mean age of 37 +/- 14.4 years (range: 13-73 years). All except one were symptomatic with a mean duration of symptoms of 10 +/- 9.4 years (range: 0.1-40 years). The indications for catheter ablation were failure of drug therapy in 71, patient's preference in 10, increased risk of sudden death in 6 and almost incessant tachycardia in 3. The radiofrequency ablation was performed using a deflectable 7 French 4 mm tip electrode catheter positioned at the mitral or tricuspid annulus. The site of the accessory pathway was localised by electrophysiological study and radiofrequency energy applied via the tip of the catheter. There were 100 accessory pathways as 10 (10%) patients had multiple accessory pathways. There were 69 (69%) left free wall, 11 (11%) posteroseptal, 13 (13%) right free wall, 6 (6%) right anteroseptal accessory pathways and one (1%) midseptal accessory pathways. Ninety-six percent (96%) of the accessory pathways were successfully ablated on the first ablation. Two of the 4 initially unsuccessful ablations were successfully reablated, giving an overall success rate of 98%. There were no major complications. In conclusion, radiofrequency catheter ablation of accessory pathways is highly successful and safe and provides a definitive cure for patients with the WPW syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)