Background: The NAUTILUS study aimed to evaluate the safety and performance of the Allegra bioprosthesis in high-risk recipients undergoing transcatheter aortic valve implantation and previously reported 30-day outcomes. In the current investigation 1-year results of the trial are presented.
Methods: Twenty-seven recipients with severe, symptomatic aortic valve stenosis at high surgical risk, who underwent treatment using the next-generation self-expanding Allegra via transfemoral approach were prospectively enrolled. Clinical endpoints assessed were: mortality, stroke, permanent pacemaker implantation, New York Heart Association class and re-hospitalizations. Prosthetic valve performance evaluation comprised of: mean gradient, effective orifice area and paravalvular leak.
Results: Patients were elderly (82.8 ± 4.2 years) and predominantly female (n = 19, 70.4%). All of them were deemed to be at high surgical risk with a mean logistic EuroSCORE of 12.5 ± 6.7. The bioprosthesis was successfully implanted in 92.6% of the cases (n = 25). At 1-year, all-cause mortality was 12.0% (n = 3) and stroke was 4.0% (n = 1). Three (12%) of patients developed complete atrioventricular block and received permanent pacemakers. 84% of patients were in New York Heart Association class II or lower. Need for subsequent hospitalization arose in 48% patients. The echocardiographic assessment confirmed an acceptable hemodynamic profile of the Allegra with low mean transprosthetic gradient (9.5 ± 3.4 mmHg), absence of severe paravalvular leak and a 20%-presence of moderate paravalvular leak.
Conclusions: The current follow-up observation study shows that the Allegra was associated with a satisfactory safety profile and hemodynamic performance at 1-year after implantation.
Keywords: Allegra; NAUTILUS clinical study; transcatheter aortic valve implantation.