Geometry is a major determinant of flow reversal in proximal aorta.
The aim of this study is to quantify aortic backward flow (BF) using phase-contrast cardiovascular magnetic resonance (PC-CMR) and to study its associations with age, indexes of arterial stiffness, and geometry. Although PC-CMR blood flow studies showed a simultaneous presence of BF and forward flow (FF) in the ascending aorta (AA), the relationship between aortic flows and aging as well as arterial stiffness and geometry in healthy volunteers has never been reported. We studied 96 healthy subjects [47 women, 39 ± 15 yr old (19-79 yr)]. Aortic stiffness [arch pulse wave velocity (PWVAO), AA distensibility], geometry (AA diameter and arch length), and parameters related to AA BF and FF (volumes, peaks, and onset times) were estimated from CMR. Applanation tonometry carotid-femoral pulse-wave velocity (PWVCF), carotid augmentation index, and time to return of the reflected pressure wave were assessed. Whereas FF parameters remained unchanged, BF onset time shortened significantly (R(2) = 0.18, P < 0.0001) and BF volume and BF-to-FF peaks ratio increased significantly (R(2) = 0.38 and R(2) = 0.44, respectively, P < 0.0001) with aging. These two latter BF indexes were also related to stiffness indexes (PWVCF, R(2) > 0.30; PWVAO, R(2) > 0.24; and distensibility, R(2) > 0.20, P < 0.001), augmentation index (R(2) > 0.20, P < 0.001), and aortic geometry (AA diameter, R(2) > 0.58; and arch length, R(2) > 0.31, P < 0.001). In multivariate analysis, aortic diameter was the strongest independent correlate of BF beyond age effect. In conclusion, AA BF estimated using PC-CMR increased significantly in terms of magnitude and volume and appeared earlier with aging and was mostly determined by aortic geometry. Thus BF indexes could be relevant markers of subclinical arterial wall alterations.
Sorbonne Universités, UPMC/Université Paris 06, UMR 7371, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; Inserm, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; CNRS, UMR 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; and Hôpital Européen Georges Pompidou, Inserm, UMR 970, Université Paris Descartes and Assistance Publique Hôpitaux de Paris, Cardiovascular Imaging Department, Paris, France.
Mourad Z
MZ
Bensalah
Sorbonne Universités, UPMC/Université Paris 06, UMR 7371, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; Inserm, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; CNRS, UMR 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; and.
Emilie
E
Bollache
Sorbonne Universités, UPMC/Université Paris 06, UMR 7371, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; Inserm, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; CNRS, UMR 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; and.
Nadjia
N
Kachenoura
Sorbonne Universités, UPMC/Université Paris 06, UMR 7371, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; Inserm, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; CNRS, UMR 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; and.
Alain
A
Giron
Sorbonne Universités, UPMC/Université Paris 06, UMR 7371, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; Inserm, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; CNRS, UMR 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; and.
Alain
A
De Cesare
Hôpital Européen Georges Pompidou, Inserm, UMR 970, Université Paris Descartes and Assistance Publique Hôpitaux de Paris, Cardiovascular Imaging Department, Paris, France.
Laurent
L
Macron
Sorbonne Universités, UPMC/Université Paris 06, UMR 7371, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; Inserm, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; CNRS, UMR 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; and.
Muriel
M
Lefort
Alban
A
Redheuil
Sorbonne Universités, UPMC/Université Paris 06, UMR 7371, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; Inserm, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; CNRS, UMR 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; and.
Alban
A
Redheuill
Sorbonne Universités, UPMC/Université Paris 06, UMR 7371, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; Inserm, UMR S 1146, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; CNRS, UMR 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France; and Hôpital Européen Georges Pompidou, Inserm, UMR 970, Université Paris Descartes and Assistance Publique Hôpitaux de Paris, Cardiovascular Imaging Department, Paris, France elie.mousseaux@egp.aphp.fr.
Elie
E
Mousseaux
D000328:Adult; D000368:Aged; D001011:Aorta / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D015999:Multivariate Analysis; D063177:Pulse Wave Analysis; D012039:Regional Blood Flow / Q000502:physiology*; D059289:Vascular Stiffness / Q000502:physiology
aging; aortic flow reversal; arterial stiffness; magnetic resonance imaging