The world upside down - after 20 years of follow-up of dextro-transposition of the great arteries.

Dextro-transposition of the great arteries (D-TGA) is a congenital heart disease (CHD) classically palliated with atrial switch (ATR-S) and nowadays corrected with arterial switch (ART-S). Our aim was to observe a group of D-TGA patients followed in an adult CHD outpatient clinic. We analyzed a group of D-TGA patients born between 1974 and 2001. Adverse events were defined as a composite of death, stroke, myocardial infarction or coronary revascularization, arrhythmia, and ventricular, baffle, or significative valvular dysfunction. A total of 79 patients were enrolled, 46% of whom were female, with a mean follow-up of 27±6 years after surgery. ATR-S was performed in 54% and ART-S in 46%; the median age at procedure was 13 months and 10 days, respectively. During follow-up, almost all ART-S remained in sinus rhythm versus 64% of ATR-S (p=0.002). The latter group had a higher incidence of arrhythmias (41% versus 3%, p<0.001), mostly atrial flutter or fibrillation; the median time to first arrhythmia was 23 years. Systemic ventricle systolic dysfunction (SVSD) was more frequent in ATR-S (41% versus 0%, p<0.001); the mean time to SVSD was 25 years. In ART-S, the most frequent complication was significant valvular regurgitation (14%). Regarding time-to-event analysis, 80% and 40% of ATR-S maintained adverse events-free after 20 and 30 years, respectively; the time-to-first adverse event was 23 years, and there was no difference compared to ART-S (Log-rank=0.596). ART-S tended to maintain more preserved biventricular function than ATR-S (Log-rank=0.055). After a long term free of adverse events, ATR-S patients experienced more arrhythmias and SVSD. ART-S complications were predominantly anastomosis-related; SVSD or arrhythmias were rare.