Artery Research

<Previous Article In Issue
Next Article In Issue>
Volume 16, Issue C, December 2016, Pages 67 - 68

8.10 BRACHIAL ARTERY FLOW-MEDIATED DILATATION: DIFFERENT PATTERNS OF WALL SHEAR RATE INCREASE DURING REACTIVE HYPERAEMIA

Authors
Kunihiko Aizawa1, Sara Sbragi2, Alessandro Ramalli3, Piero Tortoli3, Francesco Casanova1, Carmela Morizzo2, Clare Thorn1, Angela Shore1, Phillip Gates1, Carlo Palombo2
1Diabetes and Vascular Medicine Research Centre, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, UK
2Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine, University of Pisa, Italy
3Department of Information Engineering, University of Florence, Italy
Available Online 24 November 2016.
DOI
10.1016/j.artres.2016.10.066How to use a DOI?
Abstract

Background: Wall shear rate (WSR) is considered an important stimulus for flow-mediated dilatation (FMD). However, its estimation by conventional ultrasound is challenging due to inherent difficulties of velocity estimation near the arterial wall. To evaluate how WSR influences brachial artery FMD, we used a prototype Doppler ultrasound system which provides simultaneous estimates of WSR at near and far walls and continuous arterial diameter tracking.

Methods: Data from 33 young healthy individuals (27.5±4.9yrs, 19F) were analysed. FMD was assessed with a conventional reactive hyperaemia technique using Ultrasound Advanced Open Platform (ULA-OP). All acquired raw data were post-processed using custom-designed software to obtain WSR and diameter parameters.

Results: Baseline diameter and FMD were 3.29±0.45 mm and 6.54±3.54 %, respectively. During hyperaemia, we observed two distinct patterns of increased WSR: monophasic (MOP, n=15 fast increase reaching peak WSR at once) and biphasic (BIP, n=18 fast followed by slow increase before reaching peak WSR). In BIP, peak WSR (657±153 sec-1 vs 522±132 sec-1) and WSR area under the curve until peak dilation (20398±6265 au vs 13530±5592 au) were significantly greater than in MOP (both p<0.05). Absolute diameter increase was significantly greater in BIP (0.24±0.10 mm) than in MOP (0.15±0.09 mm, p<0.05). Percentage diameter increase tended to be greater in BIP (7.6±3.3 %) than MOP (5.3±3.5 %, p=0.08).

Conclusions: These results demonstrate that there are distinct WSR increase patterns during hyperaemia, and that these patterns are associated with differences in the magnitude of hyperaemic WSR. Our observations suggest that these WSR increase patterns may be associated with the subsequent brachial artery FMD response.

Open Access
This is an open access article distributed under the CC BY-NC license.

Download article (PDF)
View full text (HTML)

<Previous Article In Issue
Next Article In Issue>
Journal
Artery Research
Volume-Issue
16 - C
Pages
67 - 68
Publication Date
2016/11/24
ISSN (Online)
1876-4401
ISSN (Print)
1872-9312
DOI
10.1016/j.artres.2016.10.066How to use a DOI?
Open Access
This is an open access article distributed under the CC BY-NC license.

Cite this article

risenwbib
TY  - JOUR
AU  - Kunihiko Aizawa
AU  - Sara Sbragi
AU  - Alessandro Ramalli
AU  - Piero Tortoli
AU  - Francesco Casanova
AU  - Carmela Morizzo
AU  - Clare Thorn
AU  - Angela Shore
AU  - Phillip Gates
AU  - Carlo Palombo
PY  - 2016
DA  - 2016/11/24
TI  - 8.10 BRACHIAL ARTERY FLOW-MEDIATED DILATATION: DIFFERENT PATTERNS OF WALL SHEAR RATE INCREASE DURING REACTIVE HYPERAEMIA
JO  - Artery Research
SP  - 67
EP  - 68
VL  - 16
IS  - C
SN  - 1876-4401
UR  - https://doi.org/10.1016/j.artres.2016.10.066
DO  - 10.1016/j.artres.2016.10.066
ID  - Aizawa2016
ER  -