title: Cryopreservation procedure does not modify human carotid homografts mechanical properties: an isobaric and dynamic analysis.
abstract: The viscoelastic and inertial properties of the arterial wall are responsible for the arterial functional role in the cardiovascular system. Cryopreservation is widely used to preserve blood vessels for vascular reconstruction but it is controversially suspected to affect the dynamic behaviour of these allografts. The aim of this work was to assess the cryopreservation's effects on human arteries mechanical properties. Common carotid artery (CCA) segments harvested from donors were divided into two groups: Fresh (n = 18), tested for 24-48 h after harvesting, and Cryopreserved (n = 18) for an average time of 30 days in gas-nitrogen phase, and finally defrosted. Each segment was tested in a circulation mock, and its pressure and diameter were registered at similar pump frequency, pulse and mean pressure levels, including those of normotensive and hypertensive conditions. A compliance transfer function (diameter/pressure) derived from a mathematical adaptive modelling was designed for the on line assessment of the arterial wall dynamics and its frequency response. Assessment of arterial wall dynamics was made by measuring its viscous (eta), inertial (M) and elastic (E) properties, and creep and stress relaxation time constant (tauC and tauSR, respectively). The frequency response characterization allowed to evaluate the arterial wall filter or buffer function. Results showed that non-significant differences exist between wall dynamics and buffer function of fresh and cryopreserved segments of human CCA. In conclusion, our cryopreservation method maintains arterial wall functional properties, close to their fresh values.
authors.affiliation: Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay. dbia@fmed.edu.uy
authors.forename: Daniel
authors.initials: D
authors.lastname: Bia
authors.forename: Franco
authors.initials: F
authors.lastname: Pessana
authors.forename: Ricardo
authors.initials: R
authors.lastname: Armentano
authors.forename: Héctor
authors.initials: H
authors.lastname: Pérez
authors.forename: Sebastián
authors.initials: S
authors.lastname: Graf
authors.forename: Yanina
authors.initials: Y
authors.lastname: Zócalo
authors.forename: Maria
authors.initials: M
authors.lastname: Saldías
authors.forename: Natalia
authors.initials: N
authors.lastname: Perez
authors.forename: Oscar
authors.initials: O
authors.lastname: Alvarez
authors.forename: Walter
authors.initials: W
authors.lastname: Silva
authors.forename: Daniel
authors.initials: D
authors.lastname: Machin
authors.forename: Patricia
authors.initials: P
authors.lastname: Sueta
authors.forename: Silvia
authors.initials: S
authors.lastname: Ferrin
authors.forename: Maria
authors.initials: M
authors.lastname: Acosta
authors.forename: Inés
authors.initials: I
authors.lastname: Alvarez
mesh_terms: D002339:Carotid Arteries / Q000637:transplantation; D015925:Cryopreservation; D004548:Elasticity; D006801:Humans; D014184:Transplantation, Homologous