Aortic Stiffness and Diameter Predict Progressive Aortic Dilatation in Patients with Marfan Syndrome

Aim: Patients with Marfan syndrome may develop dissection due to progressive dilatation in the entire aorta, which is not always predictable by mere anatomic assessment of the aortic diameter, especially of the descending aorta. The aim of this study was to identify the predictive value of aortic stiffness on the occurrence of dissection and progressive aortic dilatation.

Methods And Results: In 78 non-operated patients with Marfan syndrome (mean age 31+/-8 years, mean aortic root diameter 43+/-6 mm, range 31-55 mm) aortic stiffness and diameters were assessed by magnetic resonance imaging (MRI) at multiple levels. After a median follow-up of 71 months (25-75%: 68-72 months) a second MRI was performed and the incidence of aortic dissection and progressive aortic dilatation, defined as mean aortic diameter increase >1 mm/year was determined. During follow-up, 4 (5%) of 78 patients developed an aortic dissection (1 type A, 2 type B, and 1 infra-renal dissection). Twenty (26%) of the 78 patients had progressive aortic root dilatation. There were 5 (6%) patients with progressive descending thoracic aortic dilatation and 6 (7%) with progressive abdominal aortic dilatation. Multivariate logistic regression analysis revealed that local distensibility was an independent predictor of progressive thoracic descending aortic dilatation (OR=4.14, 95% CI, 1.02-16.7). For progressive aortic root and abdominal aortic dilatation local initial diameter appeared to be the major predictor (OR=1.37, 95% CI, 1.16-1.62; OR=1.36, 95% CI, 1.09-1.69, respectively).

Conclusion: In patients with Marfan syndrome both aortic diameter and aortic distensibility are independent predictors of progressive aortic dilatation. For optimal risk assessment and monitoring of patients with Marfan syndrome, both aortic stiffness and diameter should be assessed at least annually.