Computational Analysis of Multislice CT Angiography

Abstract

In the last two decades, coronary computed tomography angiography (CTA) has been introduced as a noninvasive alternative for the assessment of coronary anatomy. Research in the field has made major progress, and landmark discoveries include the introduction and validation of patient-specific 3-D blood flow analysis, the development of adaptive finite-element models for simulating cardiovascular blood flow, the definition of physiologically realistic inflow and outflow boundary conditions, as well as the coupled description of blood flow and vessel wall dynamics. Computed CTA can provide an accurate coronary geometric model, including branching and pathology specific to a patient. Based upon this geometric information, a volumetric finite-element mesh with anisotropic refinement and boundary layers is generated in order to compute numerical results. Upon completion of the blood flow analysis, mean coronary pressure is extracted from the computer analysis performed under maximum hyperemic conditions. The noninvasive fractional flow reserve (FFRCT) is defined as the computed mean coronary pressure distal to a lesion divided by the computed mean blood pressure in the aorta under conditions of simulated maximum hyperemia. This technology has been clinically validated against invasive FFR in several studies with high sensitivity, specificity, and accuracy. The adjunction of functional and anatomical noninvasive evaluation of patients using a single MSCT study will ultimately provide a comprehensive “one-stop” noninvasive evaluation of the coronaries and will guide interventional and surgical revascularization.