Atrioventricular Nodal Reentrant Tachycardia in a Patient with Superior- Inferior Ventricles and Dextrocardia Treated with Cryoablation

A 19-year-old female underwent repair of complex congenital heart disease (atrial and ventricular septal defect with a supero-inferior ventricular relationship) in infancy. Because of recurrent palpitations she underwent an electrophysiology study. Atypical atrioventricular nodal reentrant tachycardia was diagnosed. Catheter ablation was performed successfully using cryothermal energy. The diagnostic and therapeutic approach is discussed. I n t r o d u c t I o n Symptoms of recurrent tachycardia in patients with repaired congenital heart disease are usually due to intra-atrial reentry or a previously undiagnosed accessory pathway. Atrioventricular (AV) nodal reentrant tachycardia (AVNRT) is an uncommon etiology in this context. The location of the AV node may be atypical in these patients. We report a patient with complex congenital heart disease with unusual presentation of AVNRT, who underwent successful treatment with cryoablation.