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

AIMS: 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.

METHODS AND RESULTS: 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%).

CONCLUSION: Three-dimensional TOE planimetry of aortic annulus improves the assessment of prosthesis/annulus discongruence and predicts the appearance of significant AR after TAVI.