40 years after the first atrial switch procedure in patients with transposition of the great arteries: long-term results in Toronto and Zurich

The atrial switch procedure dramatically improved the prognosis of children with complete transposition of the great arteries (TGA). Overall actuarial survival was approximately 75% after 25 years and was better in patients with simple TGA than in those with complex TGA. Mortality by any cause (16%) and cardiovascular mortality (12% and 13%) were comparable in both centers. Progressive congestive heart failure and sudden death were the principal modes of death. Most of the survivors denied any symptoms or had mild limitations in their daily activities. However, long-term problems in this growing population of adults are challenging and include late arrhythmias (up to two thirds of the patients), systemic ventricular (SV) failure, systemic atrioventricular valve regurgitation and reoperations, such as baffle reconstruction, being the most frequent. Objective assessment of SV function obtained by echocardiography is difficult. It may include fractional area change and tricuspid annular motion. Survivors after an atrial switch procedure are unique and have a good quality of life. However, the definitive and true history of the RV supporting the systemic circulation is not as yet known.