title: Constitutive description of human femoropopliteal artery aging.
abstract: Femoropopliteal artery (FPA) mechanics play a paramount role in pathophysiology and the artery's response to therapeutic interventions, but data on FPA mechanical properties are scarce. Our goal was to characterize human FPAs over a wide population to derive a constitutive description of FPA aging to be used for computational modeling. Fresh human FPA specimens ([Formula: see text]) were obtained from [Formula: see text] predominantly male (80 %) donors 54±15 years old (range 13-82 years). Morphometric characteristics including radius, wall thickness, opening angle, and longitudinal pre-stretch were recorded. Arteries were subjected to multi-ratio planar biaxial extension to determine constitutive parameters for an invariant-based model accounting for the passive contributions of ground substance, elastin, collagen, and smooth muscle. Nonparametric bootstrapping was used to determine unique sets of material parameters that were used to derive age-group-specific characteristics. Physiologic stress-stretch state was calculated to capture changes with aging. Morphometric and constitutive parameters were derived for seven age groups. Vessel radius, wall thickness, and circumferential opening angle increased with aging, while longitudinal pre-stretch decreased ([Formula: see text]). Age-group-specific constitutive parameters portrayed orthotropic FPA stiffening, especially in the longitudinal direction. Structural changes in artery wall elastin were associated with reduction of physiologic longitudinal and circumferential stretches and stresses with age. These data and the constitutive description of FPA aging shed new light on our understanding of peripheral arterial disease pathophysiology and arterial aging. Application of this knowledge might improve patient selection for specific treatment modalities in personalized, precision medicine algorithms and could assist in device development for treatment of peripheral artery disease.
authors: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA. Alexey.Kamenskiy@unmc.edu.
authors: Alexey
authors: A
authors: Kamenskiy
authors: Department of Chemical Engineering, University of Maryland, Baltimore County, MD, USA.
authors: Andreas
authors: A
authors: Seas
authors: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA.
authors: Paul
authors: P
authors: Deegan
authors: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA.
authors: William
authors: W
authors: Poulson
authors: Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE, USA.
authors: Eric
authors: E
authors: Anttila
authors: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA.
authors: Sylvie
authors: S
authors: Sim
authors: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA.
authors: Anastasia
authors: A
authors: Desyatova
authors: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA. JMacTaggart@unmc.edu.
authors: Jason
authors: J
authors: MacTaggart
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D001158:Arteries / Q000502:physiology*; D001696:Biomechanical Phenomena; D003094:Collagen / Q000378:metabolism; D004549:Elastin / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D058729:Peripheral Arterial Disease / Q000503:physiopathology; D055815:Young Adult
chemical_list: D003094:Collagen; D004549:Elastin
keywords: Biaxial testing; Constitutive modeling; Femoropopliteal artery; Mechanical properties; Peripheral artery disease; Remodeling