1.4 PROGNOSTIC VALUE OF PROXIMAL AORTA LONGITUDINAL STRAIN IN MARFAN SYNDROME

Background: Aortic root dilation and type A aortic dissection are the most common cardiovascular complications of Marfan syndrome (MFS). Current clinical management of MFS patients relies on a close follow-up of aortic root diameter and preventive aortic root surgery in case of severe or fast-progressing dilation. However, as the capacity of aortic diameter to predict type A aortic dissection is limited, new non-invasive biomarkers to improve risk stratification are needed. We investigated the capacity of proximal aorta circumferential and longitudinal strain and ascending aorta distensibility to predict aortic root diameter dilation and occurrence of major cardiovascular events in Marfan patients. Methods: Eighty-seven Marfan patients without previous cardiac/aortic surgery or dissection were prospectively included in a multicenter follow-up. Proximal aorta longitudinal and circumferential strain and distensibility were computed from baseline CMR. Results: During a follow-up of 81.6 ± 17 months, 11 patients underwent elective aortic root replacement, and 2 experienced type A aortic dissections. Mean dilation rate was 0.65 ± 0.67 mm/year and z-score growth rate 0.07 ± 0.13 1/year. In multivariable analysis, proximal aorta longitudinal strain but not circumferential strain and distensibility were independent predictors of diameter growth-rate (p = 0.001, p = 0.385 and p = 0.381, respectively), z-score growth-rate (p = 0.018, p = 0.515 and p = 0.484, respectively) and major cardiovascular events (p = 0.018, p = 0.064 and p = 0.205, respectively) corrected for demographic and clinical characteristics and baseline aortic root diameter. Conclusions: In Marfan syndrome, proximal aorta longitudinal strain is an independent predictor of aortic root dilation and major cardiovascular events beyond aortic root diameter and established risk factors.