Life expectancy of patients with Marfan syndrome has increased, due to earlier diagnosis, better familial screening, regular follow-up (FU) and timely prophylactic aortic surgery (PASu). Incidence of aortic events in affected patients recognized during childhood is unknown.

465 patients with Marfan syndrome, diagnosed before 18 year-old between 1993 and 2013 were included in the French multicenter database. Cardio-vascular events (death, aortic dissection or PASu) were recorded

FU was complete for 69.5%. A cardio-vascular event occurred in 25 patients (5.4% 95CI 3.5-7.8%), including PASu (n=20, 4.3% 95CI 2.5-6.2%), aortic dissection (n=3, 0.6% 95CI 0.0-1.4%) and deaths (n=2, 0.4% 95CI 0.0-1.0%). 16 events (64%) occurred before 19 year-old (Median 15.0, min 2.8, interquartile 11.7-16.3; PASu n=12, deaths n=2 and dissection n= 2). One sudden death occurred in a 18 y.o. girl followed until the age of 14.3 under beta-blockade treatment. A 3.4 year-old boy with a FBN1 mutation diagnosed at the age of 1.1 died from respiratory distress and viral myocarditis.

An aortic surgery was performed in 23 patients (4.9%, 95CI 3.0-6.9%), including a Bentall procedure with mechanical aortic valve in 10 (43.5%), a valve sparing surgery in the remaining 13 (56.5%) and a supra-coronary graft in 4 (17.4%, dissection: n=2 and PASu: n=2). Mean age at the date of PASu was 17.1±6.5 year-old

Events occurred before or at inclusion in the database in 8 patients (32.0%) (PASu n=5, dissection n=2, death n=1). Dissection was observed before inclusion in 2 patients out of 3 and during pregnancy in 1 patient aged 25 and lost of FU until 19 year-old. Kaplan-Meier survival estimate indicates that 95% of patients remained free from events at eighteen and 78% at thirty year-old.

Prophylactic surgery for enlarged aorta is the main cause of cardiac events in patients with Marfan syndrome diagnosed during childhood. A quarter of them have a cardiac event before thirty year-old (figure next page).