Contrast-enhanced Computed Tomography angiography (CT) is routinely used as a complementary technique to trans-thoracic echocardiography (TEE) for assessing the aorta. It provides comprehensive anatomical information and accurate measurements of the aortic root in patients with thoracic aortic aneurysms (TAA)1. The purpose of our study was to validate appropriate CT planes that match closely with reference TEE measurements.

TTE measurements of the aortic root were performed in Marfan patients with TAA, using the leading edge-to-leading edge technique in end-diastole on the parasternal longitudinal view. ECG-gated CT measurements were also obtained by two blinded observers, within one month, using the inner-to-inner technique in end-diastole by double oblique reconstruction: on 3-chamber view (3C), left ventricle-aorta view (LVAo), and strict transverse plan that is perpendicular to the two previous and passing through the maximal diameter “cusp to commissure” and “cusp to cusp” for each cusp (Fig....

44 Marfan patients (39 ±19years, 48% men) were analysed. Dilatation of the ascending aorta was maximal at the sinuses level (mean 47.5 ±5.3mm). TTE diameters were similar to 3C, LVAo (mean differences: 2.2 and -0.1mm, p=NS) and to the three “cusp to cusp” diameters (mean differences ranging from 0 to 1.1mm, p=NS), whereas “cusp to commissure” diameters were all statistically smaller than TTE (NCC 3.6mm, LCC 2.9mm and RCC 3.7mm, p≤0.01), (Fig.2 and 3). Interobserver reproducibility was high (0.81 to 0.96).

In conclusion, “cusp to commissure” diameters underestimate aortic dilatation at the level of the sinuses of Valsalva. CT aortic diameters should be measured either on the LVAo view or from “cusp to cusp”, which are the closest to the maximal aortic diameters obtained with TTE which is the reference standard for the surgery timing2.

1. Joint Task Force on the Management of Valvular Heart Disease of the European Society of C, European Association for Cardio-Thoracic S, Vahanian A, Alfieri O, Andreotti F, Antunes MJ, et al. Guidelines on the management of valvular heart disease (version 2012). European heart journal. 2012 2012/10//;33(19):2451-96. 2. Jondeau G, Detaint D, Tubach F, Arnoult F, Milleron O, Raoux F, et al. Aortic event rate in the Marfan population: a cohort study. Circulation. 2012 2012/01/17/;125(2):226-32.