Prosthesis/annulus discongruence assessed by three-dimensional transoesophageal echocardiography: A predictor of significant paravalvular aortic regurgitation after transcatheter aortic valve implantation

Abstract

Paravalvular aortic regurgitation (AR) is common after transcatheter aortic valve implantation (TAVI). This study aimed to assess the prosthesis/aortic annulus discongruence by three-dimensional (3D) transoesophageal (TOE) planimetry of aortic annulus and its impact on the occurrence of significant AR after TAVI. We included 33 patients who underwent TAVI with a balloon expandable device for severe aortic stenosis. To appraise the prosthesis/annulus discongruence, we defined a 'mismatch index' expressed as: annulus area - prosthesis area. The aortic annulus area was planimetered with 3D TOE, and approximated by circular area formula (π r(2)) using annulus diameter obtained by two-dimensional (2D) TOE. After TAVI, 13 patients (39.3%) developed significant AR (≥2/4). The occurrence of significant AR was associated to the 3D planimetered annulus area (P = 0.04), and the 'mismatch index' obtained through 3D planimetered annulus area (P = 0.03), but not to 'mismatch index' derived of 2D annulus diameter. In multivariate analysis, 'mismatch index' for 3D planimetered annulus area was the only independent predictor of significant AR (odds ratio: 10.614; 95% CI: 1.044-17.21; P = 0.04). The area under the receiver operating characteristic curve for the 'mismatch index' by the 3D planimetered annulus area was 0.76 (95% CI: 0.54-0.92), whereas for 'mismatch index' obtained by the 2D circular area was 0.36 (95% CI: 0.17-0.55). Using the 3D planimetered annulus area as the reference parameter to decide the prosthetic size, the choice would have been different in 21 patients (63%). Three-dimensional TOE planimetry of aortic annulus improves the assessment of prosthesis/annulus discongruence and predicts the appearance of significant AR after TAVI.