01.02 Geometric and Elastic Properties of the Common Carotid Artery in Vascular Ehlers-Danlos Syndrome Patients with Identified COL3A1 Mutations

Abstract

Background

Vascular Ehlers-Danlos syndrome (vEDS), an autosomal dominant inherited disorder of connective tissue, results from mutations in the gene encoding type III procollagen (COL3A1), can present with spontaneous arterial rupture or dissection. Diagnostic is based on the clinical criteria. Mutations of COL3A1 gene may be identified in about 60% case. Our study is to compare arterial geometric and elastic properties in vSED patients with identified COL3A1 mutations (COL3A1+) to unidentified COL3A1 mutations (COL3A1-).

Methods

53 vEDS patients diagnosed by clinical criteria with no previous β-blocker were included in the cross-sectional study. Mutations of COL3A1 gene was identified in 32 patients. Arterial parameters were determined with high-resolution echo-tracking system coupled with applanation tonometry. Quantitative variables were compared by general linear model ANOVA.

Results

Demographic data did not differ between COL3A1+ and COL3A1-patients. Patients with COL3A1- were significantly older than COL3A1+ patients (+7 yrs, p < 0.05). Heart rate, SBP, MBP, brachial PP, central PP, carotid diameter, distensibility, Young’s elastic modulus, carotid-femoral pulse-wave velocity were not significantly different between two groups. Carotid intima-media thickness (IMT) was significantly lower (-18%, p < 0.001) in COL3A1+ than COL3A1- patients. Carotid circumferential wall stress (σθ) was higher (+35%, p<0.001) in COL3A1+ than COL3A1- patients. After adjustment for age and blood pressure, these differences remained significant.

Conclusions

vSED patients with COL3A1+ have a lower carotid IMT associated with a higher σθ than COL3A1- patient. These results reveal the role of σθ in the pathogenesis of the vascular lesions and confirm the gold-standard of identifying COL3A1 mutations in the diagnostic of this syndrome.