Radiofrequency Catheter Ablation of Orthodromic Atrioventricular Reentrant Tachycardia in a Child with Congenitally Corrected Transposition of the Great Arteries and Atrial Septal Defect

We report a 9-year-old girl who has been diagnosed with congenitally corrected transposition of the great arteries (CCTGA) and a secundum-type atrial septal defect (ASD) with left-to-right shunting who presented with paroxysmal palpitation for two years. Her cardiac 2D electrocardiogram shows L-type transposition of the great arteries with normal left and right ventricular function. The ASD measured 10mm in diameter had adequate rim, and percutaneous device closure was the planned treatment. About a year ago, she had paroxysm of palpitation and was sent to a local hospital, where paroxysmal supraventricular tachycardia (PSVT) was documented and terminated by intravenous bolus of 6 mg adenosine. The electrocardiogram of PSVT showed regular narrow QRS-complex tachycardia at a rate of 230 beats/min. There was no evidence of ventricular preexcitation in serial ECGs during sinus rhythm.