Introduction: We describe a case of idiopathic left ventricular tachycardia originating in the posterior fascicle in a medical student labeled with epilepsy in his history. Methods: Medical student aged 24 years came to the ER aft er a guard presenting sustained palpitations lasting 10 hours, hemodynamically well supported. We tried to convert it with adenosine IV and beta-blockers, without success. Aft er I.V Amiodarone, ventricular captures and fusions confi rmed ventricular tachycardia, subsequently yielding conversion to sinus rhythm. Laboratory tests were normal. Echocardiography revealed normal left ventricle and ejection fraction of 60%. Verapamil was administrated at discharge, but because of hypotension and psychological eff ects, discontinuation of antiarrhythmic was wanted. Results: We performed electrophysiological study with three-dimensional electroanatomical mapping system using CARTO 3 (Biosens Webster). The mechanism of arrhythmia has been identified as a reentry circuit using posterior inferior fascicle of the left ventricle. The radiofrequency applications effectuated at the Purkinje fibers of the posterior fascicle interrupted his tachycardia and made it non-inducible at programmed stimulation before and aft er administration of Isoprenaline. Conclusions: Idiopathic ventricular tachycardia originating from the posterior inferior left ventricular fascicle usually occurs in young male adults. Clinically it is manifested by paroxysmal episodes of palpitations. Episodes often occur at rest, but triggers such as stress and exercise can induce episodes of TV. Radiofrequency ablation is ideal for definitive treatment of arrhythmia.