title: Differences in aortic vortex flow pattern between normal and patients with stroke: qualitative and quantitative assessment using transesophageal contrast echocardiography.
abstract: The flow in the aorta forms a vortex, which is a critical determinant of the flow dynamics in the aorta. Arteriosclerosis can alter the blood flow pattern of the aorta and cause characteristic alterations of the vortex. However, this change in aortic vortex has not yet been studied. This study aimed to characterize aortic vortex flow pattern using transesophageal contrast echocardiography in normal and stroke patients. A total of 85 patients who diagnosed with ischemic stroke and 16 normal controls were recruited for this study. The 16 normal control subjects were designated as the control group, and the 85 ischemic stroke patients were designated as the stroke group. All subjects underwent contrast transesophageal echocardiography (TEE), and particle image velocimetry was used to assess aortic vortex flow. Qualitative and quantitative analyses of vortex flow morphology, location, phasic variation, and pulsatility were undertaken and compared between the groups. In the control group, multiple irregularly-shaped vortices were observed in a peripheral location in the descending thoracic aorta. In contrast, the stroke group had a single, round, merged, and more centrally located aortic vortex flow. In the quantitative analysis of vortex, vortex depth, which represents the location of the major vortex in the aorta, was significantly higher in the control group than in the stroke group (0.599 ± 0.159 vs. 0.522 ± 0.101, respectively, P = 0.013). Vortex relative strength, which is the pulsatility parameter of the vortex itself, was significantly higher in the stroke group than in the control group (0.367 ± 0.148 vs. 0.304 ± 0.087, respectively, P = 0.025). It was feasible to visualize and quantify the characteristic morphology and pulsatility of the aortic vortex flow using contrast TEE, and aortic vortex pattern significantly differed between normal and stroke patients.
authors.affiliation: Division of Cardiology, Yeungnam University Hospital, Yeungnam University College of Medicine, Daegu, Korea.
authors.forename: Jang-Won
authors.initials: JW
authors.lastname: Son
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Yonsei Cardiovascular Hospital, Yonsei University College of Medicine, 250 Seungsanno, Seodaemun-gu, Seoul, 120-752, Korea. grhong@yuhs.ac.
authors.forename: Geu-Ru
authors.initials: GR
authors.lastname: Hong
authors.affiliation: New York University, New York, NY, USA.
authors.forename: Woosol
authors.initials: W
authors.lastname: Hong
authors.affiliation: School of Medicine, University of Queensland, Herston, QLD, Australia.
authors.forename: Minji
authors.initials: M
authors.lastname: Kim
authors.affiliation: Siemens Medical Solutions, Mountain View, CA, USA.
authors.forename: Helene
authors.initials: H
authors.lastname: Houle
authors.affiliation: Department of Cardiovascular Imaging, Piedmont Heart Institute, Atlanta, GA, USA.
authors.forename: Mani A
authors.initials: MA
authors.lastname: Vannan
authors.affiliation: Department of Engineering and Architecture, University of Trieste, Trieste, Italy.
authors.forename: Gianni
authors.initials: G
authors.lastname: Pedrizzetti
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Yonsei Cardiovascular Hospital, Yonsei University College of Medicine, 250 Seungsanno, Seodaemun-gu, Seoul, 120-752, Korea.
authors.forename: Namsik
authors.initials: N
authors.lastname: Chung
mesh_terms: D000328:Adult; D000368:Aged; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002545:Brain Ischemia / Q000000981:diagnostic imaging* / Q000503:physiopathology; D016022:Case-Control Studies; D003287:Contrast Media / Q000008:administration & dosage*; D017548:Echocardiography, Transesophageal; D005240:Feasibility Studies; D005260:Female; D005466:Fluorocarbons / Q000008:administration & dosage*; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011673:Pulsatile Flow; D012039:Regional Blood Flow; D015203:Reproducibility of Results; D020521:Stroke / Q000000981:diagnostic imaging* / Q000503:physiopathology; D016277:Ventricular Function, Left
chemical_list: D003287:Contrast Media; D005466:Fluorocarbons; C042852:perflutren
keywords: Aorta; Stroke; Vortex