Idiopathic ventricular tachycardia: feasibility and efficacy of catheter ablation.

Idiopathic ventricular tachycardia is a well described syndrome of both left and right ventricular origin. This study reports the feasibility and efficacy of catheter ablation in this entity. Fourteen patients (mean age 30 +/- 10 years of age) and six patients (mean age 51 +/- 9 years of age) underwent endocardial catheter ablation with either direct-current shocks and radiofrequency energy, respectively. Earliest right and left ventricular activation and endocardial mapping during tachycardia were made to localize the site of ventricular tachycardia origin. The overall clinical efficacy was 93% for direct-current method with a mean number of shocks of 3.3 +/- 0.9/patient after a mean follow-up of 38 +/- 25 months. Radiofrequency ablation achieved an overall clinical efficacy of 83.6% with a mean of 3.2 pulses/patient during a follow-up of 10.5 +/- 4 months. The isoenzyme MB fraction of peak creatine kinase after ablation was less than 5%. There were no complications in any patient who underwent radiofrequency energy. Endocardial catheter ablation is feasible in patients with idiopathic ventricular tachycardia. Both methods are highly effective but radiofrequency energy is most desirable because of its lack of barotrauma, and may be considered as early therapy.