Abstract 4688: The Impact of Marfan Syndrome on Arterial Stiffness and Endothelial Function: The Role of Matrix Metalloproteinases
Background: Marfan syndrome is characterised by high risk of aortic dissections and increased cardiovascular risk. However, the impact of Marfan syndrome on endothelial function and arterial stiffness is unclear, while the role of matrix metalloproteinases is unknown. We examined the impact of Marfan syndrome on the elastic properties of the arterial tree, and vascular endothelial function, and we evaluated the potential role of matrix metalloproteinases in these effects.
Methods: The study population consisted of 17 subjects with Marfan syndrome, aged 26.6±2.3 years old, with BMI 20.5±1.03Kg/m2 and 22 healthy individuals matched for gender, age (26.4±0.78 years old, p=NS) and BMI (22.4±0.86 Kg/m2). Arterial stiffness was evaluated by measuring carotid-femoral pulse wave velocity (PWV), while augmentation pressure and augmentation index (AIx) were also determined, as measures of arterial wave reflections. Endothelial function was evaluated by determining flow mediated dilation (FMD) in the brachial artery while matrix metalloproteinase 9 (MMP-9) levels were determined by ELISA.
Results: Patients with Marfan syndrome had significantly lower pulse pressure in the radial artery (41.0±1.07mmHg) compared to controls (51.3±4.4mmHg). In addition, patients had higher AIx (17.6±2.4%) and augmentation pressure (5.44±0.65mmHg) compared to controls (7.72±3.43% and 2.41±1.14mmHg respectively, p<0.05 for both). However, the difference in PWV between patients and controls did not reach statistical significance (6.33±0.33 vs 5.96±0.23m/s respectively, p=NS). Patients with Marfan syndrome had lower FMD (2.05±1.13%) and higher plasma MMP-9 (827±70ng/ml) compared to controls (6.8±2.3% p<0.05 and 326±50ng/ml, p<0.01).
Conclusions: Marfan syndrome is associated with increased MMP-9 levels, as well as with elevated augmentation index and augmentation pressure compared to healthy individuals, matched for age, gender and body mass index. Moreover, flow-mediated dilation is also impaired in these subjects. These findings suggest that Marfan syndrome directly affects the elastic properties and endothelial function of the arterial tree, with matrix metalloproteinases being important mediators in the pathophysiology of this syndrome.