Patient-specific Hemodynamics of Severe Carotid Artery Stenosis Before and After Endarterectomy Examined by 4D Flow MRI

• Published in: Scientific reports Vol. 9; no. 1; pp. 18554 - 8
• Main Authors: Ko, Seungbin, Lee, Jeesoo, Song, Simon, Kim, Doosang, Lee, Sang Hyung, Cho, Jee-Hyun
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 06.12.2019; Nature Publishing Group
• Subjects: 59/57; 692/4019/592/75/593/1353; 692/699/75/593/2100; Aged; Blood Flow Velocity - physiology; Carotid arteries; Carotid artery; Carotid Artery, Internal - diagnostic imaging; Carotid Artery, Internal - physiopathology; Carotid Artery, Internal - surgery; Carotid Stenosis - diagnosis; Carotid Stenosis - physiopathology; Carotid Stenosis - surgery; Endarterectomy, Carotid; Hemodynamics; Humanities and Social Sciences; Humans; Imaging, Three-Dimensional - methods; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Male; Models, Cardiovascular; multidisciplinary; Phantoms, Imaging; Postoperative Period; Regional Blood Flow - physiology; Retrospective Studies; Science; Science (multidisciplinary); Severity of Illness Index; Shear Strength - physiology; Shear stress; Stenosis; Stress, Mechanical; Surgery; Treatment Outcome; Veins & arteries
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-019-54543-x

Carotid endarterectomy (CEA) influences the carotid endoluminal anatomy, which results in hemodynamic changes before and after surgery. We investigated the hemodynamics of severe carotid artery stenosis before and after conventional endarterectomy with/without patch repair. An in vitro experiment utilizing carotid phantoms, which underwent a procedure that emulated CEA with/without the patch repair, was performed with a high-spatiotemporal resolution using 4D flow MRI. We evaluated an abnormal region of carotids, which consists of the normalized time-averaged wall shear stress (NTA|WSS|) and the oscillatory shear index (OSI), to account for continuous high-shear regions (high NTA|WSS| and low OSI) and chaotic low-shear regions, i.e., stenosis-prone regions (low NTA|WSS| and high OSI). The use of normalized hemodynamic parameters (e.g., NTA|WSS|) allowed comparison of diverse cases with different conditions of hemodynamics and vessel geometry. We observed that the stenosis-prone regions of the carotids with patches were noticeably larger than the corresponding regions in no-patch carotids. A large recirculating flow zone found in the stenosis-prone region of the internal carotid artery (ICA) of the postoperative carotids with patches partially blocks the flow path into ICA, and consequently the flow rate was not recovered after surgery unlike an expectation.