title: Local versus global aortic pulse wave velocity in early atherosclerosis: An animal study in ApoE-/--mice using ultrahigh field MRI.
abstract: Increased aortic stiffness is known to be associated with atherosclerosis and has a predictive value for cardiovascular events. This study aims to investigate the local distribution of early arterial stiffening due to initial atherosclerotic lesions. Therefore, global and local pulse wave velocity (PWV) were measured in ApoE-/- and wild type (WT) mice using ultrahigh field MRI. For quantification of global aortic stiffness, a new multi-point transit-time (TT) method was implemented and validated to determine the global PWV in the murine aorta. Local aortic stiffness was measured by assessing the local PWV in the upper abdominal aorta, using the flow/area (QA) method. Significant differences between age matched ApoE-/- and WT mice were determined for global and local PWV measurements (global PWV: ApoE-/-: 2.7±0.2m/s vs WT: 2.1±0.2m/s, P<0.03; local PWV: ApoE-/-: 2.9±0.2m/s vs WT: 2.2±0.2m/s, P<0.03). Within the WT mouse group, the global PWV correlated well with the local PWV in the upper abdominal aorta (R2 = 0.75, P<0.01), implying a widely uniform arterial elasticity. In ApoE-/- animals, however, no significant correlation between individual local and global PWV was present (R2 = 0.07, P = 0.53), implying a heterogeneous distribution of vascular stiffening in early atherosclerosis. The assessment of global PWV using the new multi-point TT measurement technique was validated against a pressure wire measurement in a vessel phantom and showed excellent agreement. The experimental results demonstrate that vascular stiffening caused by early atherosclerosis is unequally distributed over the length of large vessels. This finding implies that assessing heterogeneity of arterial stiffness by multiple local measurements of PWV might be more sensitive than global PWV to identify early atherosclerotic lesions.
authors.affiliation: Department of Experimental Physics V, University of Würzburg, Würzburg, Germany.|Department of Cardiology, University Heart Center, University Hospital Zurich, Zurich, Switzerland.|Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland.
authors.forename: Alexander
authors.initials: A
authors.lastname: Gotschy
authors.affiliation: Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany.|Comprehensive Heart Failure Center / Deutsches Zentrum für Herzinsuffizienz, University of Würzburg, Würzburg, Germany.
authors.forename: Wolfgang R
authors.initials: WR
authors.lastname: Bauer
authors.affiliation: Department of Experimental Physics V, University of Würzburg, Würzburg, Germany.
authors.forename: Patrick
authors.initials: P
authors.lastname: Winter
authors.affiliation: Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany.|Comprehensive Heart Failure Center / Deutsches Zentrum für Herzinsuffizienz, University of Würzburg, Würzburg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Nordbeck
authors.affiliation: Department of Experimental Physics V, University of Würzburg, Würzburg, Germany.
authors.forename: Eberhard
authors.initials: E
authors.lastname: Rommel
authors.affiliation: Department of Experimental Physics V, University of Würzburg, Würzburg, Germany.|Comprehensive Heart Failure Center / Deutsches Zentrum für Herzinsuffizienz, University of Würzburg, Würzburg, Germany.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Jakob
authors.affiliation: Department of Experimental Physics V, University of Würzburg, Würzburg, Germany.
authors.forename: Volker
authors.initials: V
authors.lastname: Herold
mesh_terms: D000818:Animals; D001011:Aorta / Q000473:pathology / Q000503:physiopathology*; D001057:Apolipoproteins E / Q000235:genetics*; D050197:Atherosclerosis / Q000473:pathology / Q000503:physiopathology*; D017353:Gene Deletion; D008279:Magnetic Resonance Imaging / Q000379:methods; D051379:Mice; D008810:Mice, Inbred C57BL; D063177:Pulse Wave Analysis / Q000379:methods; D059289:Vascular Stiffness
chemical_list: D001057:Apolipoproteins E