Outcomes of transcatheter aortic valve replacement in patients with bicuspid aortic valve

Background

Bicuspid aortic valve (BAV) is a leading cause of aortic stenosis (AS) in younger patients. Recently, the anatomical understanding of BAV has increased, and BAV subtypes are known to also be found in calcific aortic stenosis of the elderly. With the expansion of transcatheter aortic valve replacement (TAVR) into lower-risk populations, the proportion of patients with BAV undergoing TAVR is expected to increase. However, robust long-term outcome data in this population remain limited.

Objectives

To determine the prevalence of BAV among patients undergoing TAVR and to evaluate procedural and long-term clinical outcomes compared with tricuspid aortic valve (TAV) anatomy.

Methods

We retrospectively analyzed all consecutive patients undergoing TAVR at our center between 2013 and 2022. BAV morphology was assessed by pre-procedural computed tomography and classified according to the Sievers classification. Patients with missing imaging, inadequate image quality, or relevant anatomical abnormalities were excluded. The primary endpoint was 3-year all-cause mortality. Secondary endpoints included VARC-3 composite endpoints technical failure and device failure. Multivariable Cox regression was performed to adjust for baseline differences.

Results

Among 3,961 screened patients, 3,816 were included in the final analysis. BAV was identified in 263 patients (6.9%), predominantly Sievers type 1 (90.1%), most commonly with a raphe between the left and right coronary cusps.

Compared with patients with tricuspid aortic valves, those with BAV were younger (78.2 vs. 81.9 years, p<0.01) and had a lower Society of Thoracic Surgeons risk score (2.1 vs. 3.4, p<0.01), as well as fewer comorbidities, including diabetes mellitus, hypertension, coronary artery disease, and chronic kidney disease.

At 3 years, all-cause mortality was significantly lower in the BAV group (25.1% vs. 37.7%; hazard ratio [HR] 0.53; 95% confidence interval [CI] [0.40–0.72]; follow-up rate 93%). After multivariable adjustment, BAV remained independently associated with lower mortality (adjusted HR 0.57; 95% CI [0.43–0.77]). Technical failure (4.9% vs. 4.1%), device failure (16.0% vs. 11.6%), and procedural mortality (1.5% vs. 0.6%) were numerically higher in patients with BAV, primarily driven by paravalvular regurgitation and higher post-procedural mean transvalvular gradients.

Conclusions

In this large single-center cohort, BAV was present in approximately 7% of patients undergoing TAVR. Although procedural complexity and device failure were slightly increased, TAVR was associated with favorable long-term survival in patients with BAV. The observed mortality benefit is likely attributable to their younger age and lower comorbidity burden. These findings support the feasibility of TAVR in selected patients with BAV, while underscoring the need for dedicated long-term evaluation in this anatomically distinct population.All-cause mortality after three years