Successful scartectomy and cryoablation for ventricular tachycardia occurring late after correction of tetralogy of Fallot

: A 26-year-old man had a total repair of tetralogy of Fallot at 1 year of age, and had redo surgery for restenosis of the right ventricular outflow tract and small residual VSD at 11 years of age. After the second operation, AV block developed and an endocardial pacemaker system was implanted. For the last 3 years, he had mild febrile episodes, cough, occasional hemoptysis and paroxysmal ventricular tachycardia. Because of his refractory tachycardia and suspected infective endocarditis, he was admitted for further study. Blood culture revealed Peptostreptococcus, echocardiogram showed vegetation around intravenous pacing lead, and electrophysiological study demonstrated delayed potential on the left side of the right ventricular outflow tract. He underwent scartectomy and cryoablation of the focus of the tachycardia which was reconfirmed by epicardial and endocardial mapping during the operation, which involved removal of the endocardial lead and new outflow tract patch repair. His postoperative course was uneventful without any antiarrhythmic drugs. Pathological examination of the scar showed myocardial fibrosis and replacement by fatty tissue which was different from the pathological characters of the arrythmogenic right ventricular dysplasia.