Michael Tse-Yin Lu MD, Presenter: Nothing to Disclose

Stephen Crook, Abstract Co-Author: Nothing to Disclose

Michael D. Hope MD, Abstract Co-Author: Nothing to Disclose

Previous work suggests that ascending aortic (AsAo) aneurysm with bicuspid aortic valve (BAV) may be asymmetric, which is unexpected if intrinsic aortic wall fragility were the sole etiology for dilation. We have used our database of thoracic cross-sectional imaging to assess whether there is asymmetric AsAo dilation of the AsAo with BAV.

CTA and MRA images of the thorax were retrospectively reviewed for 98 patients divided into 4 subgroups: tricuspid aortic valve (TAV) controls, BAV controls, nonstenotic TAV with aortic dilation, and BAV with aortic dilation. Orthogonal diameters at 5 standard levels in the AsAo were measured along with the length of the outer and inner curvatures of the AsAo on three-dimensional (3D) reformats in “candy-cane” orientation.

TAV and BAV controls were similar, with normal orthogonal AsAo measurements and ratios of outer to inner AsAo curvature (1.55 and 1.54 respectively). TAV with aortic dilation had increased outer to inner AsAo curvature ratio (1.70, p < 0.01), but the asymmetric dilation was most pronounced in BAV with aortic dilation (ratio of 2.01, p < 0.001 compared to TAV with aortic dilation). This asymmetric dilation was seen in both BAV patients with and without aortic valvular disease.

Asymmetric dilation of the AsAo is seen with BAV, with bulging of the outer aortic curvature.

Eccentric systolic flow and elevated shear stress are reported where we demonstrate asymmetric dilation. In this context, our results suggest hemodynamic forces contribute to AsAo dilation with BAV.

Lu, M, Crook, S, Hope, M, Asymmetric Ascending Aortic Dilation with Bicuspid Aortic Valve.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11003408.html Accessed May 8, 2025