Post-implant transcatheter aortic prosthesis deformation: tricuspid versus bicuspid valve

OBJECTIVES: We sought to assess whether post-implant transcatheter aortic valve prosthesis multidetector computed characteristics differ between patients with native tricuspid and bicuspid aortic valve stenosis, as well as the effect on valve performance and clinical implications. METHODS: We analysed 100 consecutive post-implant multidetector computed tomography scans to assess self-expandable prosthesis non-uniform expansion at 6 pre-specified valvular levels, and other specific parameters, including valvular and perivalvular thrombosis at 6 months follow-up. Echocardiographic prosthesis performance and clinical outcome were also evaluated. RESULTS: Mean eccentricity was significantly higher in the bicuspid group (0.43 (0.09) vs 0.37 (0.08), P = 0.005, bicuspid vs tricuspid); valvular and perivalvular thrombosis were also significantly more frequent in the bicuspid than in the tricuspid group (81% vs 36.9%, P = 0.031); there was no significant difference in terms of mean prosthetic gradient at follow-up between (7.31 (5.53 mmHg) vs 7.09 (3.05 mmHg), P = 0.825); EOAi (indexed effective orifice area) was also similar between bicuspid and tricuspid (1.08 (0.12 cm2) vs 1.03 (0.13 cm2), P = 0.101), with no significant changes compared to discharge. However, the bicuspid valve was associated with a significantly higher risk of adverse events (HR: 3.72, 95% CI: 1.07-13.4, P = 0.027). CONCLUSIONS: Higher level of eccentricity, which indicates prosthesis deformation, is often detected in bicuspid valves. Although echocardiographic performance was not affected, this might have led to an increased incidence of thrombosis at valvular and perivalvular levels and worse outcomes.