Clinical outcomes of bicuspid versus tricuspid aortic valve stenosis after transcatheter aortic valve replacement with self-expandable valves

Background There is a lack of available data on specific prognostic comparisons between transcatheter aortic valve replacement (TAVR) using self-expandable valves (SEV) in patients with stenotic Type 0, Type 1 bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV). Objectives To evaluate the association between aortic valve morphology and outcomes following self-expandable TAVR. Methods Consecutive patients with aortic stenosis(AS) undergoing self-expandable TAVR were enrolled and categorized into three groups (Type 0/Type 1 BAV or TAV) according to the Sievers classification. The primary endpoint was a composite of all-cause mortality and rehospitalization for heart failure (HF) within 2 years. Secondary outcomes included procedural complications and major cardiovascular events observed in clinical follow-ups. Clinical outcomes at 2 years following TAVR were compared among three groups using Kaplan-Meier curve and multivariable Cox proportional hazards regression models. Results A total of 344 AS patients (Type 0: 86; Type 1: 109; TAV: 149) were enrolled. The presence of moderate or severe paravalvular leak (PVL) was significantly higher in patients with Type 0 and Type 1 BAV versus TAV (10.47% vs. 16.51% vs. 6.71%, p = 0.043). All-cause 30-day mortality (2.33% vs. 0.92% vs. 2.68%, p = 0.626) and 2-year mortality (3.49% vs. 5.50% vs. 6.71%, p = 0.657) was comparable among the three groups. However, rehospitalization for HF within 2 years was significantly higher in Type 1 BAV (11.63% vs. 20.18% vs. 8.72%, p = 0.020). Multivariate Cox analysis showed that a higher STS score, Type 1 BAV morphology and excess leaflet calcification (≥ median calcium volume (CV) of the entire population) were independent predictors for HF rehospitalization. Additional intragroup Kaplan‒Meier analysis showed that excess leaflet calcification could predict higher long-term mortality and rehospitalization risk for HF(HR (95% CI): 3.430 (1.166–10.090), log rank p = 0.017) in Type 1 BAV patients. Conclusion Outcomes of self-expandable TAVR in BAV-AS patients might vary depending on valve subtypes. BAV patients with excess leaflet calcification and a raphe, especially calcified, had an increased risk of moderate PVL and HF readmission in mid-to-long term follow-ups.