Abstract 11582: Prognostic Implications of Anatomical Aortic Valve Area in Patients with Bicuspid Aortic Stenosis by Three-Dimensional Transesophageal Echocardiography

Abstract

Background: Three-dimensional (3D) transesophageal echocardiography (TEE) provides high-resolution images of aortic valve area (AVA) in patients with bicuspid aortic stenosis (AS). However, the correlation with pressure gradient compared with conventional echocardiographic indices and prognostic implications of 3D TEE derived valve area (AVA 3DTEE ) has not been evaluated. Therefore, we assessed the disease severity and the prognostic value of AVA 3DTEE in patients with bicuspid AS. Methods: We retrospectively analyzed 105 patients with at least mild bicuspid AS (peak aortic velocity >2.5m/sec) and LVEF ≥50% (mean transaortic pressure gradient 46±17 mm Hg) underwent transthoracic echocardiography, two-dimensional (2D) and 3D TEE between 2012 and 2019. AVA was measured using (i) the continuity equation (CE) obtained with transthoracic echocardiography, (ii) planimetric 2D TEE, and (iii) volumetric 3D TEE. Cardiac events were defined as surgical or transcatheter aortic valve replacement and/or aortic replacement, heart failure admission, or cardiac death. Results: AVA 3DTEE was larger than AVA CE (mean difference 0.21±0.03, P <0.001), and smaller than AVA 2DTEE (mean difference 0.11±0.02, P <0.001). AVA 3DTEE had an excellent correlation with mean transaortic pressure gradient (r=0.91, P <0.001), whereas AVA 2DTEE and AVA CE showed lower correlations (r=0.81 and r=0.59, both P <0.001). AVA 3DTEE significantly reduced the proportion of inconsistent AS grading, compared with AVA CE (6% versus 17%, P <0.001). During a follow-up period (median, 853 days; range 513 to 1287 days), 101 surgical or transcatheter aortic valve replacement and/or aortic replacement, 6 heart failure admission, or 1 cardiac death occurred. AVA 3DTEE ≤1cm 2 was an independent predictor of cardiac events (adjusted hazard ratio (HR) 2.40, (1.41 to 4.09), P =0.001) and AVA 3DTEE of 1 cm 2 was the optimal cutoff value for predicting cardiovascular events with sensitivity of 71% and specificity of 100%. Conclusions: AVA measured by 3D TEE has a good correlation with mean transaortic pressure gradient and improved the hitherto inconsistent AS grading. AVA 3DTEE ≤1cm 2 is an important predictor for cardiac events of patients with bicuspid AS.