Dissection in Marfan syndrome: the importance of the descending aorta.

AIMS: To better characterize patients with Marfan syndrome who have survived an acute aortic dissection and to estimate the risks of events in the descending aorta. Up until now, this portion of the aorta has not been well studied but is gaining importance due to improved patient survival.

METHODS AND RESULTS: We report a retrospective cohort of 100 Marfan patients who survived an aortic dissection. Dissection occurred in either the ascending aorta (AscAo) (n = 37), the descending aorta (DescAo) (n = 20), or both (As + DescAo, n = 43). During a mean follow-up of 9.8 ± 6.0 years (complete for 88% of the patients), 17 patients died and 52 had a clinical event (new aortic dissection, surgery, ischaemia, haemorrhage), 60% of which involved the descending aorta. Event-free survival was similar whatever the location of the aortic dissection. However, a better event-free survival was observed when no dissected portion of the aorta remained after surgery, which was the case in 62% (23/37) of the AscAo patients (30% incurred an event vs. 86%; P = 0.008 by log-rank test). Interestingly, the diameter of the ascending aorta was below the surgical threshold in 60% of the patients who incurred a dissection of the descending aorta, and within the normal range in 25%.

CONCLUSION: The descending aorta may dissect whatever the diameter of the ascending aorta. The descending aorta is the location of most late clinical events after any dissection of the aorta. The rate of clinical events is much lower when all the dissected aorta has been removed in patients with AscAo dissection.