title: Pulmonary artery relative area change is inversely related to ex vivo measured arterial elastic modulus in the canine model of acute pulmonary embolization.
abstract: A low relative area change (RAC) of the proximal pulmonary artery (PA) over the cardiac cycle is a good predictor of mortality from right ventricular failure in patients with pulmonary hypertension (PH). The relationship between RAC and local mechanical properties of arteries, which are known to stiffen in acute and chronic PH, is not clear, however. In this study, we estimated elastic moduli of three PAs (MPA, LPA and RPA: main, left and right PAs) at the physiological state using mechanical testing data and correlated these estimated elastic moduli to RAC measured in vivo with both phase-contrast magnetic resonance imaging (PC-MRI) and M-mode echocardiography (on RPA only). We did so using data from a canine model of acute PH due to embolization to assess the sensitivity of RAC to changes in elastic modulus in the absence of chronic PH-induced arterial remodeling. We found that elastic modulus increased with embolization-induced PH, presumably a consequence of increased collagen engagement, which corresponds well to decreased RAC. Furthermore, RAC was inversely related to elastic modulus. Finally, we found MRI and echocardiography yielded comparable estimates of RAC. We conclude that RAC of proximal PAs can be obtained from either MRI or echocardiography and a change in RAC indicates a change in elastic modulus of proximal PAs detectable even in the absence of chronic PH-induced arterial remodeling. The correlation between RAC and elastic modulus of proximal PAs may be useful for prognoses and to monitor the effects of therapeutic interventions in patients with PH.
authors.affiliation: Department of Biomedical Engineering, University of Wisconsin-Madison, 1550 Engineering Drive, Madison, WI 53706-1609, USA.
authors.forename: Lian
authors.initials: L
authors.lastname: Tian
authors.affiliation: School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive, Madison, WI 53706-1102, USA.
authors.forename: Heidi B
authors.initials: HB
authors.lastname: Kellihan
authors.affiliation: Department of Biomedical Engineering, University of Wisconsin-Madison, 1550 Engineering Drive, Madison, WI 53706-1609, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Henningsen
authors.affiliation: Department of Biomedical Engineering, University of Wisconsin-Madison, 1550 Engineering Drive, Madison, WI 53706-1609, USA.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Bellofiore
authors.affiliation: Department of Biomedical Engineering, University of Wisconsin-Madison, 1550 Engineering Drive, Madison, WI 53706-1609, USA.
authors.forename: Omid
authors.initials: O
authors.lastname: Forouzan
authors.affiliation: Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792-3252, USA.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Roldán-Alzate
authors.affiliation: Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792-3252, USA.
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Consigny
authors.affiliation: Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792-3252, USA.
authors.forename: McLean
authors.initials: M
authors.lastname: Gunderson
authors.affiliation: Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792-3252, USA.
authors.forename: Seth H
authors.initials: SH
authors.lastname: Dailey
authors.affiliation: Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792-3252, USA.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Francois
authors.affiliation: Department of Biomedical Engineering, University of Wisconsin-Madison, 1550 Engineering Drive, Madison, WI 53706-1609, USA. Electronic address: chesler@engr.wisc.edu.
authors.forename: Naomi C
authors.initials: NC
authors.lastname: Chesler
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D055119:Elastic Modulus; D005260:Female; D006976:Hypertension, Pulmonary / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D011651:Pulmonary Artery / Q000503:physiopathology*
keywords: Elastic modulus; Embolization; Pulmonary hypertension; Relative area change