PURPOSE: To assess blood flow velocities and spatial distribution of aortic Reynolds numbers in vivo using flow-sensitive magnetic resonance imaging (MRI) and probe for flow instabilities along the aorta based on an empirical model for physiological pulsatile blood flow. MATERIALS AND METHODS: Thirty young healthy volunteers were examined by flow-sensitive MRI at eight imaging planes distributed along the thoracic aorta. Flow, Womersley, Strouhal, Reynolds, and critical Reynolds numbers were calculated and used to assess the presence of flow instabilities. RESULTS: The average peak Reynolds number was higher in the ascending (≈4500) and descending aorta (≈4200) than in the aortic arch (≈3400). According to the calculated critical Reynolds numbers, flow instabilities were prominent in the ascending (14/30 volunteers) and descending aorta (22/30 volunteers) but not in the aortic arch (3/30 volunteers). A significant difference (P < 0.05) in supracritical peak Reynolds numbers was observed between genders. The supracritical Reynolds number, indicating flow instabilities, significantly correlated (P < 0.05) with body weight (r = 0.34), aortic diameter (r = 0.48), and cardiac output (r = 0.53). CONCLUSION: Flow-sensitive MRI was used to indirectly assess the presence of flow instabilities in vivo. The results in volunteers indicate the presence of flow instabilities in the young healthy aorta with a higher prevalence for men than women.
PURPOSE: To assess blood flow velocities and spatial distribution of aortic Reynolds numbers in vivo using flow-sensitive magnetic resonance imaging (MRI) and probe for flow instabilities along the aorta based on an empirical model for physiological pulsatile blood flow. MATERIALS AND METHODS: Thirty young healthy volunteers were examined by flow-sensitive MRI at eight imaging planes distributed along the thoracic aorta. Flow, Womersley, Strouhal, Reynolds, and critical Reynolds numbers were calculated and used to assess the presence of flow instabilities. RESULTS: The average peak Reynolds number was higher in the ascending (≈4500) and descending aorta (≈4200) than in the aortic arch (≈3400). According to the calculated critical Reynolds numbers, flow instabilities were prominent in the ascending (14/30 volunteers) and descending aorta (22/30 volunteers) but not in the aortic arch (3/30 volunteers). A significant difference (P < 0.05) in supracritical peak Reynolds numbers was observed between genders. The supracritical Reynolds number, indicating flow instabilities, significantly correlated (P < 0.05) with body weight (r = 0.34), aortic diameter (r = 0.48), and cardiac output (r = 0.53). CONCLUSION: Flow-sensitive MRI was used to indirectly assess the presence of flow instabilities in vivo. The results in volunteers indicate the presence of flow instabilities in the young healthy aorta with a higher prevalence for men than women.
Authors: Emilie Bollache; Pim van Ooij; Alex Powell; James Carr; Michael Markl; Alex J Barker Journal: Int J Cardiovasc Imaging Date: 2016-07-19 Impact factor: 2.357
Authors: Monica Emendi; Francesco Sturla; Ram P Ghosh; Matteo Bianchi; Filippo Piatti; Francesca R Pluchinotta; Daniel Giese; Massimo Lombardi; Alberto Redaelli; Danny Bluestein Journal: Ann Biomed Eng Date: 2020-08-17 Impact factor: 3.934
Authors: Pablo Lamata; Alex Pitcher; Sebastian Krittian; David Nordsletten; Malenka M Bissell; Thomas Cassar; Alex J Barker; Michael Markl; Stefan Neubauer; Nicolas P Smith Journal: Magn Reson Med Date: 2013-11-18 Impact factor: 4.668
Authors: Srikara V Peelukhana; Yanmin Wang; Zachary Berwick; Jarin Kratzberg; Joshua Krieger; Blayne Roeder; Rachel E Clough; Albert Hsiao; Sean Chambers; Ghassan S Kassab Journal: Ann Biomed Eng Date: 2016-08-10 Impact factor: 3.934