Liqing Peng, Presenter: Nothing to Disclose

Xiao-Yi Chen, Abstract Co-Author: Nothing to Disclose

Jian-Qun Yu MD, Abstract Co-Author: Nothing to Disclose

Zhi-Gang Yang, Abstract Co-Author: Nothing to Disclose

Bicuspid aortic stenosis (BAS) has been a relative contraindication to transcatheter aortic valve implantation (TAVI), but small series of patients with severe BAS successfully treated with TAVI were reported recently. We sought to assess the dynamic features of aortic annulus of BAS throughout cardiac cycle by dual source computed tomography (DSCT).

Thirty -one patients (15 males and 16 females；mean age：69.1±5.3 years，range：60–82 years) with severe BAS who underwent retrospectively ECG-gated DSCT angiography were included. The images were reconstructed into 10 phases at 10% step of R-R interval. The image quality was evaluated with a 3-points scoring method (3 points: good image quality free of artifact; 2 points: adequate image quality for evaluation with mild artifact; 1 point: inadequate image quality due to severe artifact). Minor aortic annular diameter (AAD-min), major aortic diameter (AAD-maj), aortic annular perimeter (AAP) and aortic annular area (AAA) were measured in each phase. AAP derived AAD (AAD-PD) and AAA derived AAD (AAD-AD) were calculated using formula C = πD and s = π(D/2)2, respectively. The absolute and relative difference of all parameters throughout the cardiac cycle were calculated with (maximum-minimum) and [(maximum-minimum)/minimum] multiplied by 100%.

Best image quality was in 20%, 30%, 60% and 70% R-R intervals in the majority of patients (96.8%, 30/31) during cardiac cycle. In all patients, AAD-min, AAD-maj, AAP and AAA varied during cardiac cycle, and AAD-maj was greater than AAD-min throughout the cardiac cycle (p < 0.0001). The relative differences of AAD-min, AAD-maj, AAD-PD and AAD-AD were 19.6±12.9%, 15.7±8.0%, 9.6±6.2% and 9.8±3.1%, respectively; while the absolute difference of which were 4.0±2.5mm, 3.7±1.5mm, 2.5±0.9mm and 2.6±1.2 mm, respectively (p<0.001).

In patients with BAS, aortic annulus is oval and its shape changes during cardiac cycle. The difference of AAD-PD throughout cardiac cycle is relative smaller. Thus, AAP might be the most proper parameter for estimating aortic annulus size before TAVI. Considering image quality, mid-late systole and mid-diastole were more reliable for evaluation.

Finding out dynamic features of aortic annulus of BAS may help precisely estimate aortic annulus size, and decrease TAVI procedure related complications.

Peng, L, Chen, X, Yu, J, Yang, Z, Evaluation of Dynamic Features of Aortic Annulus in Patients with Bicuspid Aortic Stenosis (BAS) throughout Cardiac Cycle by Dual Source Computed Tomography (DSCT): Implications for Transcatheter Aortic Valve Implantation (TAVI).  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14005883.html