Left Common Carotid Artery Biomechanical Properties in Individuals over 80 years: Women Have Stiffer Vessels

Abstract

Considering the longevity of the worldwide population, the cardiovascular diseases deserve particular attention, especially the carotid artery disease in the ≥80-year-old population. The stiffness of the common carotid artery, for example, has been showed in numerous clinical studies as a marker of increased risk of stroke, dementia, and depression. Besides, with the emergence of new surgical techniques such as the transcarotid artery revascularization that uses the common carotid artery as a workstation, the biomechanical and histological features of this vessel, more than ever, must be detailed. Left common carotid artery fragments from 9 cadaver donors (≥80years old) were evaluated. Biomechanical (failure stress, tension, and strain) and histological (percentage of collagen and elastic fibers) features of these samples were analyzed with special focus on gender differences. Statistically significant differences in biomechanical and histological features between the genders were observed. The percentage of collagen fiber in intima (P=0.008) and media (P=0.041) layers was significantly lower in men than in women. A higher elasticity (failure strain) of the specimens in male gender was also observed (P=0.025). No significant difference was observed in the layers thickness between the genders regardless which part of the arterial wall was considered. These biomechanical and histological findings could be the responsible for the higher left common carotid artery stiffness observed among ≥80-year-old women when compared with men in numerous clinical studies in literature.