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Agatston Calcium Score (CT): Explanation and Clinical Context The Agatston Score is a quantitative measure of coronary artery calcium (CAC) obtained from non-contrast CT scans. It is calculated by multiplying the area of each calcified lesion by a density factor derived from the peak Hounsfield Unit (HU) within that lesion. The sum of all lesions' scores gives the total Agatston Score. Higher scores correlate with gr
Aortic Distensibility Index (ADI): Explanation and Clinical Context The Aortic Distensibility Index (ADI) is a measure of aortic elasticity, calculated using the change in aortic diameter during the cardiac cycle relative to pulse pressure. It reflects the ability of the aorta to expand and recoil with each heartbeat. Higher ADI values indicate a more compliant aorta, while lower values suggest increased stiffness, w
Aortic Stiffness Index (ASI): Explanation and Clinical Context The Aortic Stiffness Index (β) is a non-invasive echocardiographic measure of the intrinsic stiffness of the ascending aorta. It reflects the mechanical properties of the aortic wall and is calculated using systolic and diastolic blood pressures and the corresponding aortic diameters. An increased ASI indicates reduced aortic compliance and is associated