Case 3
A 15-year-old boy with a history of Rastelli procedure using a Hancock valve conduit for congenitally corrected transposition of great arteries, ventricular septal defect and pulmonary atresia underwent ablation for the complaint of palpitations for the last 6 months. The EnSite™ NavX Precision system (St. Jude Medical St. Paul, MN, USA) is used as three dimensional mapping system and TacticathTM Quartz Contact Force (St. Jude Medical St. Paul, MN, USA) with Agilis™ NxT Steerable Introducer for mapping and ablation procedure. Selective coronary angiography was performed as catheter could not be positioned into the coronary sinus despite multiple attempts which revealed that coronary veins were opened separately without confluence of the coronary sinus. The Duodecapolar Steerable catheter (Medtronic, USA) was placed in the right atrium. Since the stable atrium potential could not be obtained, the transesophageal electrode (Esolo FIAB, Italy) was advanced into the esophagus towards the left atrium neighborhood via the nasal route. The tachycardia with 1:1 VA relationship was induced by single extra stimulus and catheter manipulation in the patient. Tachycardia was interrupted with entrainment mapping, and tachycardia was terminated by administration of adenosine. Activation and voltage mapping were performed during tachycardia in order to evaluate the scar areas in the atrium (figure 2a). Diagnostic maneuvers revealed AVRT with earliest atrial activity during tachycardia localized left posteroseptal region. Catheter was advanced into left atrium via patent foramen ovale, and then early atrial activity of the left atrium was mapped during tachycardia, -35 ms atrial activation was obtained in the left posterior region. Ablation was performed successfully without any complications.