This study evaluated the cost of performing radiofrequency catheter ablation in Japanese patients with paroxysmal supraventricular tachycardia refractory to antiarrhythmic drug therapy in comparison with the cost of continuing pharmacologic treatment. Twenty patients (mean age 44 +/- 14 years) underwent successful ablation: 15 patients with Wolff-Parkinson-White syndrome and five with atrioventricular nodal reentrant tachycardia. The mean duration of symptoms was 77 +/- 60 months. The patients had been treated with 2.6 +/- 1.7 antiarrhythmic drugs before undergoing ablation. Charges derived from hospital bills were compared with the outpatient charges for the year before ablation. The mean hospital stay for the ablation procedure was 4.3 +/- 0.5 days. The mean total charge for ablation was 982,806 yen +/- 103,195, and 5.7 +/- 0.7 times the outpatient charges in the previous year. The majority of radical cure charges were the costs of the electrode catheters used in the ablation procedure. All patients had a successful outcome and required no additional antiarrhythmic drug therapy. If medical treatment were continued without ablation, the mean total life-expectancy charges were estimated at 7,064,726 yen +/- 3,116,621, 41.0 +/- 19.2 times the outpatient charges. The total life charges of medical treatment were significantly more than the total ablation charges (p < 0.001). This study suggests that radiofrequency catheter ablation is of clinical benefit in treating paroxysmal supraventricular tachycardia, and markedly reduces the cost of definitive therapy. This strategy appears to be more economical than pharmacologic treatment.