Midterm Outcome of Primary Arterial Switch Operation Beyond Six Weeks of Life in Children With Transposition of Great Arteries and Intact Ventricular Septum

Background: We have previously reported our experience in primary arterial switch operation (ASO) in children more than six weeks with transposition of great arteries and intact ventricular septum (TGA/IVS). The upper age limit for performing an ASO in these children is not yet settled and reports regarding outcome of ASO in these children are few. In this prospective observational study, we report the midterm results of children with TGA-IVS older than six weeks undergoing primary ASO. Methods: A total of 109 children aged more than 6 weeks with median age of 60 days (range 42-3,000 days), with regressed left ventricle underwent primary ASO. Extracorporeal membrane oxygenation was used in 20% (22 of 109) of them; 90.8% (99 of 109) of children who survived were prospectively followed, with a mean follow-up of 28 months (range 18-84 months). Results: Two late deaths occurred, and survival in the remainder was estimated to be 98% at seven years. The incidence of aortic regurgitation (AR) was found to have a decreasing trend with freedom from AR approaching 100% by 34 months. The left ventricular shape and function returned to normal within one to three months following surgery. None of these children had any rhythm disturbances or evidence of myocardial ischemia. Conclusions: Primary ASO can be safely performed in children with regressed ventricle, irrespective of age with encouraging results. The midterm results of these children are comparable in terms of survival and freedom from complications associated with preserved ventricle.