Radiofrequency catheter ablation of tachyarrhythmias--adult and paediatric experience

Until recently, curative therapy for supraventricular tachycardia (SVT) was possible only with map-guided cardiac surgery. The ability to ablate permanently the reentrant circuit responsible for tachycardia using radiofrequency electrical current (RF) delivered through a catheter has now allowed cure of SVT by non-surgical means. We present our initial experience with this technique in both adult and paediatric patients.

In 53 patients of median age 32 years, 56 radiofrequency catheter ablation procedures were performed for control of tachyarrhythmias. Fourteen patients were aged 18 years or less. Indications for RF ablation were SVT due to an accessory pathway (n = 27), SVT due to atrioventricular junctional reentry (AVJRT) (n = 22), incessant SVT (n = 2), ventricular tachycardia (n = 2), and uncontrolled atrial fibrillation (n = 3). General anaesthesia was used in 88% of procedures. Ablation was preceded by electrophysiological testing to confirm tachycardia mechanism in all cases.

The ablation procedure was completely successful in 49/56 cases (87.5%) and partially successful in another two cases. Only five procedures (9%) failed. Median procedure time was two hours, median fluoroscopy time was 24 min, and the median number of RF applications was four. There were no major differences in results comparing adult and paediatric patients. A transient ulnar nerve palsy was the only major complication observed. After a follow-up of one to 15 months, tachycardia has recurred in two patients (4%). Of the total 53 patients, 90.5% are currently asymptomatic and off all cardiac drug therapy. RF catheter ablation appears to be an effective, curative, and relatively safe alternative to long term drug therapy in the management of troublesome SVT.