Anatomic and procedural predictors of paravalvular aortic regurgitation after implantation of the Medtronic CoreValve bioprosthesis

Abstract

Objectives: The purpose of this study was to determine the predictors of aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI).

Background: TAVI has been associated with a high rate of paravalvular regurgitation, usually mild. Nevertheless, moderate to severe regurgitations still occur and may have negative clinical consequences.

Methods: Fifty patients with severe aortic stenosis were recruited and underwent successful TAVI with the Medtronic CoreValve bioprosthesis through the transfemoral route. The end point of this study is the early occurrence of significant AR, defined as the occurrence of grade II or more AR by post-procedural aortography.

Results: The study population's mean age was 80.5 ± 7.9 years, with a mean aortic valve area of 0.64 ± 0.17 cm². Post-procedural AR was absent in 3 patients and was grade I in 27 patients, grade II in 13 patients, and grade III in 7 patients. Using univariate analysis, the chance of significant AR increased with increasing angle of left ventricular outflow tract to ascending aorta (∠LVOT-AO) (odds ratio: 1.24, p < 0.001). For the depth of the device in relation to the noncoronary cusp, there was a minimum chance of AR corresponding to depth = 9.5 mm (odds ratio: 1.1, p = 0.01). Using multivariate analysis, we found a greater chance of significant AR with a greater angle (odds ratio: 1.24, p = 0.001), and that the chance of significant AR is a minimum when depth of the device in relation to the noncoronary cusp is ∼10 mm (odds ratio: 1.1, p = 0.024). A predictive model was generated, and if 2 ×∠LVOT-AO + (depth to noncoronary cusp - 10)² ≥ 50, the likelihood of occurrence of significant AR could be predicted with a sensitivity of 85% and a specificity of 87%.

Conclusions: The occurrence of significant AR after TAVI can be predicted by anatomic and procedural variables. A model such as that presented can be used to select suitable patients for this procedure and guide operators during implantation of the device.