The mechanical properties of elastic arteries in Ehlers-Danlos Syndrome

Objective:To study whether measurements of wall mechanics can be used as an indicator of disturbed vessel wall integrity and predictor of vessel fragility in Ehlers-Danlos Syndrome (EDS).Methods:The wall mechanics of the abdominal aorta (AO) and common carotid artery (CCA) were estimated from the indices Ep (pressure strain elastic modulus) and stiffness (β) in twelve individuals with EDS of different subtypes and compared with the results of a healthy reference population. Ep and β were calculated from diameter and pulsatile diameter change determined non-invasively with the aid of an ultrasonic echo-tracking system and blood pressure obtained by the auscultatory method.Results:Compared with normal individuals and their confidence intervals, subjects with EDS had unaltered diameter, Ep and β in the AO, as well as in the CCA. Analysis of covariance (ANCOVA) also showed unaltered results. AO: diameter (males p = 0.66, females p = 0.27), Ep (males p = 0.81, females p = 0.27) and β (males p = 0.95, females p = 0.12). CCA: diameter (males p = 0.36, females p = 0.46), Ep (males p = 0.93, females p = 0.48) and β (males p = 0.86, females p = 0.47).Conclusions:This investigation could not demonstrate any alteration in wall mechanics as a sign of disturbed vessel wall integrity of elastic arteries in EDS. This might indicate that the structural defect in the arterial wall collagen, and thus the tendency to vessel fragility, cannot be revealed under normal physilogical pressure conditions