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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Aged, Arterial Pressure, Computed Tomography Angiography, Coronary Angiography, Coronary Artery Disease, Coronary Circulation, Coronary Stenosis, Coronary Vessels, Female, Fractional Flow Reserve, Myocardial, Humans, Hydrodynamics, Hyperemia, Male, Middle Aged, Models, Cardiovascular, Patient-Specific Modeling, Plaque, Atherosclerotic, Predictive Value of Tests, Retrospective Studies, Risk Assessment, Risk Factors, Rupture, Spontaneous, Stress, Mechanical, Vascular Calcification.
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Are computational fluid dynamic measures of wall shear stress related to coronary lesion characteristics? Context: To assess the distribution of pressure and shear-related forces acting on atherosclerotic plaques and their association with lesion characteristics using coronary CT angiography (cCTA)-based computational fluid dynamics (CFD) model of epicardial coronary arteries. Patient-specific models of epicardial coronary arteries were reconstructed from cCTA in 80 patients (12 women, 63.8±9.0 years). The pressure and wall shear stress (WSS) in left anterior descending coronary arteries were assessed using CFD. High-risk plaques were defined as the presence of at least one of the following adverse plaque characteristics: low-density plaque, positive remodelling, napkin-ring sign and spotty calcification. At resting condition, 39.5% of stenotic segments (% diameter stenosis 52.3±14.4%) were exposed to high WSS (>40 dyne/cm(2)). When the stenotic lesion was subdivided into three segments, the distribution of WSS was different from that of pressure change and its magnitude was highest at minimal lumen area (p<0.001). High pressure gradient, proximal location, small lumen and short length were independent determinants of WSS (all p<0.05). The plaques exposed to the highest WSS tertile had a significantly greater proportion of high-risk plaques. The addition of WSS to % diameter stenosis significantly improved the measures of discrimination and reclassification of high-risk plaques (area under the curves from 0.540 to 0.718, p=0.031; net reclassification index 0.827, p<0.001).
assistant
The cCTA-based CFD method can improve the identification of high-risk plaques and the risk stratification for coronary artery disease patients by providing non-invasive measurements of WSS affecting coronary plaques. Final Decision: yes