A 22-year old female Caucasian underwent an EPS due to episodes of palpitations with 12-lead electrocardiogram (ECG) documented regular, narrow QRS-complex tachycardia. Baseline ECG showed normal sinus rhythm without ventricular pre-excitation. Her medical history revealed no significant comorbidity. Physical examination on admission was without any pathology. Echocardiography done prior to the EPS showed structurally normal heart. An EPS was performed with the patient in a non-sedated state. Quadripolar diagnostic catheters JSN 5F (St. Jude Medical, St. Paul, MN, USA) were positioned in right ventricular apex and His area, and steerable decapolar catheter EZ Steer (Biosense Webster, Diamond Bar, CA, USA) was positioned into coronary sinus. At baseline, sinus cycle length, AH and HV intervals were within normal range. During the EPS, existence of dual AV nodal physiology was found (jump noted at programmed pacing interval 500/260 ms from the right atrium with the echo beat) and clinical narrow QRS tachycardia was induced during programmed stimulation of right atrium. The diagnosis of typical (slow-fast) AVNRT was made using standard manoeuvres: overdrive stimulation from the right ventricle (VAV pattern, post-pacing interval—tachycardia cycle length > 115 ms, ventriculo-atrial interval < 30 ms) ()., Despite using long steerable sheath (Agilis™ NxT, Abbot) and both right and left-sided (using antegrade approach), multiple RF ablations reaching total of >15 min of RF energy application (temperature controlled mode, 50 W, 60°C) in the triangle of Koch region, with 4-mm tip non irrigated catheter (Blazer II Standard Curve, Boston Scientific, USA) as well as achieving junctional rhythm repeatedly (>10 min in total) (), AVNRT was still inducible. AV junctional tachycardia was excluded with overdrive pacing from the right atrium (), there was still evidence of dual AV node physiology, while diagnosis of AVNRT was repeatedly proven with right ventricular overdrive pacing Six weeks later, repeated EPS using three-dimensional electroanatomical mapping system was scheduled due to AVNRT inducibility at the end of the 1st procedure. During the repeated procedure, there was no sign/proof of conduction through the slow pathway nor could AVNRT be induced neither in the baseline settings nor during isoproterenol infusion (up to 16 µg per minute) (). Hence, the procedure was aborted. In addition, the patient did not have any palpitations between the two EPS. Moreover, the patient, with no antiarrhythmic drug prescribed, did not have palpitations during 12-month follow-up period after the 2nd EPS or any tachycardia on 7-day Holter-ECG done 12 months after the 2nd EPS.