The purpose of this paper is to report our experience with endocardial catheter ablation in the recurrent episodes of paroxysmal supraventricular tachycardia in ten patients. All cases were referred because previous drug trials had failed to control arrhythmia. In four patients with Wolff Parkinson White syndrome, the ablation was used in the accessory pathway, in five patients in the his bundle region, and one patient in the AV perinodal region. The follow-up ranges from 4 to 15 months. We had a complete success rate of 40% and a partial success in other 40%. We did not have any complications during the procedures.