A Bicuspid Aortic Valve Imaging Classification for the TAVR Era

Abstract

Objectives: This study sought to evaluate transcatheter aortic valve replacement (TAVR) in bicuspid aortic valve (BAV) aortic stenosis (AS), with a particular emphasis on TAVR-directed bicuspid aortic valve imaging (BAVi) of morphological classification.

Background: TAVR has been used to treat BAV-AS but with heterogeneous outcomes and uncertainty regarding the relevance of morphology.

Methods: In 14 centers in the United States, Canada, Europe, and Asia, 130 BAV-AS patients underwent TAVR. Baseline cardiac computed tomography (CT) was analyzed by a dedicated Corelab. Outcomes were assessed in line with Valve Academic Research Consortium criteria.

Results: Bicommissural BAV (vs. tricommissural) accounted for 68.9% of those treated in North America, 88.9% in Europe, and 95.5% in Asia (p = 0.003). For bicommissural bicuspids, non-raphe type (vs. raphe type) BAV accounted for 11.9% of those treated in North America, 9.4% in Europe, and 61.9% in Asia (p < 0.001). Overall rates of 30-day mortality (3.8%) and cerebrovascular events (3.2%) were favorable and similar among anatomical subsets. The rate of new permanent pacemaker insertion was high (26.2%) and similar between balloon-expandable (BE) and self-expanding (SE) designs (BE: 25.5% vs. SE: 26.9%; p = 0.83); there was a trend to greater permanent pacemaker insertion in BE TAVR in the presence of coronary cusp fusion BAV morphology. Paravalvular aortic regurgitation (PAR) ≥ moderate was 18.1% overall but lower at 11.5% in those with pre-procedural CT. In the absence of pre-procedural CT, there was an excess of PAR in BE TAVR that was not the case in those with a pre-procedural CT; SE TAVR required more post-dilation. Predictors of PAR included intercommissural distance for bicommissural bicuspids (odd ratio [OR]: 1.37; 95% confidence interval [CI]: 1.02 to 1.84; p = 0.036) and lack of a baseline CT for annular measurement (OR: 3.03; 95% CI: 1.20 to 7.69; p = 0.018).

Conclusions: In this multicenter study, TAVR achieved favorable outcomes in patients with pre-procedural CT, with the exception of high permanent pacemaker rates for all devices and shapes.

Keywords: TAVI; TAVR; aortic stenosis; aortic valve replacement; bicuspid aortic valve; transcatheter aortic valve implantation; transcatheter aortic valve replacement.