Τίτλος:
Time course of flow-induced adaptation of carotid artery biomechanical
properties, structure and zero-stress state in the arteriovenous shunt
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Numerous studies have provided evidence of diameter adaptation secondary
to flow-overload. but with ambiguous findings vis a vis other
morphological parameters and information on the biomechanical aspects of
arterial adaptation is rather incomplete. We examined the time course of
large-artery biomechanical adaptation elicited by long-term
flow-overload in a porcine shunt model between the carotid artery and
ipsilateral jugular vein. Post-shunting, the proximal artery flow was
doubled and retained so until euthanasia (up to three months
post-operatively), without pressure change. This hemodynamic stimulus
induced lumen diameter enlargement, accommodated by elastin
fragmentation and connective tissue accumulation. as witnessed by
optical and confocal microscopy. Heterogeneous mass growth of the
adventitia was observed at the expense of the media. associated with
declining residual strains and opening angle at three months. The in
vitro elastic properties of shunted arteries determined by
inflation/extension testing were also modified, with the thickness
pressure curves shifted to larger thicknesses and the diameter pressure
curves shifted to larger diameters at physiologic pressures, resulting
in normalization of intramural and shear stresses within fifteen and
thirty days. respectively. We infer that the biomechanical adaptation in
moderate flow-overload leads to normalization of intimal shear, without,
however, restoring compliance and distensibility at mean in vivo
pressure to control levels.
Συγγραφείς:
Kritharis, Eleftherios P.
Giagini, Athina T.
Kakisis, John D.
and Dimitriou, Constantinos A.
Stergiopulos, Nikos
Tsangaris,
Sokrates
Sokolis, Dimitrios P.
Λέξεις-κλειδιά:
Arteriovenous shunt; remodeling; biomechanical properties; opening
angle; elastin; collagen
DOI:
10.3233/BIR-2012-0602
