Artery Research (Dec 2009)

5.1 ASSESSMENT OF THE ARTERIAL WALL BEHAVIOR ALONG THE COMMON CAROTID ARTERY AT THE LEVEL OF A PLAQUE ACCORDING TO ARTERIAL STIFFNESS GRADIENT

  • H. Beaussier,
  • I. Masson,
  • O. Naggara,
  • D. Calvet,
  • R. Joannides,
  • E. Guegan-Massardier,
  • E. Gérardin,
  • E. Bozec,
  • P. Boutouyrie,
  • S. Laurent

DOI
https://doi.org/10.1016/j.artres.2009.10.159
Journal volume & issue
Vol. 3, no. 4

Abstract

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Background: We previously described longitudinal strain gradient named bending strain (BS), along the common carotid artery (CCA) with two distinct patterns (Paini, Stroke 2007, Beaussier, Hypertension 2008): Pattern A (larger radial strain at the plaque level than at adjacent CCA) and its opposite, Pattern B. Aim: To assess the role of change in CCA thickness (IMT) and medial diameter (D) during the cardiac cycle at the level of plaques according to functional patterns of BS. Method: 45 CCA were analysed at the level of the plaque in 26 patients. Mechanical parameters were measured at 128 sites on a 4 cm long CCA segment by an echotracking system (ArtLab®). Plaque composition was determined by magnetic resonance imaging (MRI). For each plaque, systolo(s)-diastolic(d) variation of IMT and D were calculated. We obtained ΔIMT ((IMTs - IMTd)/IMTd), ΔDiameter ((Ds - Dd)/Dd) and ratio R (ΔIMT/ΔD). Results: R did not significantly differ according to remodeling pattern neither to plaque composition. Plaques exhibiting Pattern B (n=25) were characterized by an R 73 % higher than plaques exhibiting Pattern A (n=20) (5.9 ± 3.0 versus 3.4 ± 1.6, p<0.005). In other words, IMT strain is disproportionately larger than diameter strain among Pattern B than among pattern A. Conclusion: The arterial stiffness gradient at the level of the plaque may influence the arterial wall behavior: an inward BS may be associated with exaggerated compressibility and local stresses within the wall in comparison to an outward BS with reduced local stresses.