Objective To characterise patients with trisomy 21 (Down syndrome, DS) based on the data of the German National Register for Congenital Heart Defects, to identify changes in the availability of surgical therapy over time and to analyse the impact of these changes on developing Eisenmenger syndrome (ES) as well as survival.

Methods Out of 1549 patients with DS with congenital heart disease in the National Register for Congenital Heart Defects, 894 patients (55% female, mean age 17.5 years) had a post-tricuspid shunt lesion (atrioventricular septal defect 69.5%, ventricular septal defect 27.7%, patent arterial duct 2.6%) and were included in the current study.

Results The likelihood of being treated interventionally or surgically before the age of 1 year increased significantly over time. In parallel, the likelihood of developing ES decreased over time (53% birth cohort during 1950s/1960s vs 0.5% birth cohort during 2000–2009, p<0.0001). Overall survival after 1, 10, 20 and 40 years was 96.8%, 94.1%, 92.6% and 75.5%, respectively. Patients with ES had a significantly worse survival compared with those without ES (HR 18.1; 95% CI 7.2 to 45.4; p<0.0001).

Conclusions The availability of surgical correction was associated with a decrease in the likelihood of developing ES. Patients with DS still have reduced survival prospects compared with the general population, but this effect is largely driven by patients developing ES who still have a very poor prognosis.