ELEVATED HYPEREMIC MICROVASCULAR RESISTANCE IS ASSOCIATED WITH LOWER CORONARY WALL SHEAR STRESS IN PATIENTS WITH NON-OBSTRUCTIVE CORONARY ARTERY DISEASE

Although experimental studies suggest that low and oscillatory wall shear stress (WSS) promotes plaque transformation to a more vulnerable phenotype, this relationship has not been examined in human atherosclerosis progression. Thus, the aim of this investigation was to examine the association between oscillatory WSS, in combination with WSS magnitude, and coronary atherosclerosis progression. We hypothesized that regions of low and oscillatory WSS will demonstrate progression towards more vulnerable lesions, while regions exposed to low and non-oscillatory WSS will exhibit progression towards more stable lesions. Patients ( n = 20) with non-flow-limiting coronary artery disease (CAD) underwent baseline and six-month follow-up angiography, Doppler velocity and radiofrequency intravascular ultrasound (VH-IVUS) acquisition. Computational fluid dynamics models were constructed to compute time-averaged WSS magnitude and oscillatory WSS. Changes in VH-IVUS-defined total plaque and constituent areas were quantified in focal regions (i.e. sectors; n = 14 235) and compared across haemodynamic categories. Compared with sectors exposed to low WSS magnitude, high WSS sectors demonstrated regression of total plaque area ( p < 0.001) and fibrous tissue ( p < 0.001), and similar progression of necrotic core. Sectors subjected to low and oscillatory WSS exhibited total plaque area regression, while low and non-oscillatory WSS sectors demonstrated total plaque progression ( p < 0.001). Furthermore, compared with low and non-oscillatory WSS areas, sectors exposed to low and oscillatory WSS demonstrated regression of fibrous ( p < 0.001) and fibrofatty ( p < 0.001) tissue and similar progression of necrotic core ( p = 0.82) and dense calcium ( p = 0.40). Herein, we demonstrate that, in patients with non-obstructive CAD, sectors subjected to low and oscillatory WSS demonstrated regression of total plaque, fibrous and fibrofatty tissue, and progression of necrotic core and dense calcium, which suggest a transformation to a more vulnerable phenotype.

Download Full-text

Development of Framework to Examine the Focal Association Between Wall Shear Stress and Coronary Artery Disease Progression in the Clinical Setting

Volume 1A: Abdominal Aortic Aneurysms; Active and Reactive Soft Matter; Atherosclerosis; BioFluid Mechanics; Education; Biotransport Phenomena; Bone, Joint and Spine Mechanics; Brain Injury; Cardiac Mechanics; Cardiovascular Devices, Fluids and Imaging; Cartilage and Disc Mechanics; Cell and Tissue Engineering; Cerebral Aneurysms; Computational Biofluid Dynamics; Device Design, Human Dynamics, and Rehabilitation; Drug Delivery and Disease Treatment; Engineered Cellular Environments ◽

10.1115/sbc2013-14476 ◽

2013 ◽

Cited By ~ 1

Author(s):

Lucas H. Timmins ◽

David S. Molony ◽

Parham Eshtehardi ◽

Michael C. McDaniel ◽

John N. Oshinski ◽

...

Keyword(s):

Coronary Artery Disease ◽

Shear Stress ◽

Coronary Artery ◽

Wall Shear Stress ◽

Plaque Progression ◽

Clinical Investigations ◽

Coronary Lesions ◽

Wall Shear ◽

Coronary Events ◽

Artery Disease

Natural history data on clinical coronary artery disease (CAD) indicates that there is a critical need to prospectively identify rapidly progressing and vulnerable coronary lesions that may cause potentially fatal acute coronary events [1]. Recent prospective clinical investigations have evaluated the value of wall shear stress (WSS) as a prognostic marker for identifying rapidly progressing coronary lesions [2,3]. Data indicate that low WSS is associated with significant plaque progression, while regions of high WSS are associated with plaque regression and phenotypic transformation towards a more vulnerable lesion. While these studies provided unprecedented data on the role of hemodynamic-induced mechanical forces in lesion dynamics, they were limited by a lack of focal understanding of the association between WSS and plaque progression. Specifically, despite the understanding that WSS and plaque progression are heterogeneous around the artery’s circumference, in each image slice WSS values were spatially averaged around the circumference and correlated with average values for changes in virtual histology-intravascular ultrasound (VH-IVUS) defined plaque constituent areas.

Download Full-text