Advanced Postprocessing of Cardiac CTA

Abstract

Commercially available workstations have software packages to provide volumetric analysis for cardiac CTA. In children, it is best to obtain the data prospectively to reduce radiation exposure. The rapid heart rate of infants results in data and phases of a larger portion of the cardiac cycle than in adults with the same amount of padding. End-systolic and end-diastolic volumes are obtained easily for both right and left ventricles. The typical part of the phase to obtain the end-diastolic data is at 85–90 % of the cardiac cycle. The typical part of the phase to obtain the end-systolic data is at 45–55 % of the cardiac cycle. Once volumes have been determined for end systole and end diastole, the ejection fraction and stroke volume can be calculated and provided as part of the report. It is helpful to divide the end-diastolic and end-systolic volumes by body surface area to provide indexed volumes. Indexed volumes are obtained by dividing the gross end-diastolic and end-systolic volume of the right and left ventricles by the body surface area (Figs. 3.1, 3.2 and Table 3.1).