OBJECTIVES - The aim of this study was to compare 1-year outcomes after transcatheter aortic valve replacement (TAVR) in low surgical risk patients with bicuspid aortic stenosis to patients with tricuspid aortic stenosis.

BACKGROUND - The pivotal TAVR trials excluded patients with bicuspid aortic valves. The Low Risk Bicuspid Study 30-day primary endpoint of death or disabling stroke was 1.3%.

METHODS - The Low Risk Bicuspid Study is a prospective, single-arm, TAVR trial that enrolled patients from 25 U.S. sites. A screening committee confirmed bicuspid anatomy and valve classification on computed tomography using the Sievers classification. Valve sizing was by annular measurements. An independent clinical events committee adjudicated all serious adverse events, and an independent core laboratory assessed all echocardiograms. The 150 patients from the Low Risk Bicuspid Study were propensity matched to the TAVR patients in the randomized Evolut Low Risk Trial using the 1:1 5- to-1-digit greedy method, resulting in 145 pairs.

RESULTS - All-cause mortality or disabling stroke at 1 year was 1.4% in the bicuspid and 2.8% in the tricuspid group (P = 0.413). A pacemaker was implanted in 16.6% of bicuspid and 17.9% of tricuspid patients (P = 0.741). The effective orifice area was similar between groups at 1 year (2.2 ± 0.7 cm2 vs 2.3 ± 0.6 cm2, P = 0.677) as was the mean gradient (8.7 ± 3.9 mm Hg vs 8.5 ± 3.1 mm Hg, P = 0.754). Fewer patients in the bicuspid group had mild or worse paravalvular leak (21.3% vs 42.6%, P < 0.001).

CONCLUSIONS - There were no significant differences in clinical or forward flow hemodynamic outcomes between the propensity-matched groups at 1 year.