Eight-year results after aortic valve replacement with the Freestyle stentless bioprosthesis

We sought to describe the hemodynamic and clinical outcomes for the Freestyle aortic root bioprosthesis (Medtronic, Inc, Minneapolis, Minn) in a large multicenter cohort prospectively followed for 8 years.

A total of 700 patients (651 [93%] >60 years of age) at 8 centers in North America were followed prospectively after aortic valve replacement with the Freestyle stentless bioprosthesis; the implant technique was subcoronary in 500, total root in 162, and root inclusion in 38. Follow-up was 3395 patient-years (4.9 +/- 2.3 years per patient). Clinical and echocardiographic follow-up was prospectively obtained at yearly intervals.

For the subcoronary, total root, and root inclusion groups, actuarial freedom from valve-related death was 96.8% (SE 3.0%), 92.3% (SE 7.7%), and 90.9% (SE 11.2%), respectively, and freedom from structural deterioration was 98.6% (SE 2.0%), 100.0% (SE 0.0%), and 100.0% (SE 0.0%), respectively. Hemodynamics remained excellent at 6 years. Freedom from moderate or more aortic regurgitation was 86.0% (SE 5.1%), 98.7% (SE 3.9%), and 97.3% (SE 6.6%), respectively. Gradients were slightly lower (P =.0009), and the effective orifice area (P =.02) and freedom from aortic regurgitation were slightly higher (P =.03) with total root than subcoronary implantation.

The Freestyle stentless aortic root bioprosthesis is a versatile option for aortic valve replacement. Measures of clinical outcomes and prosthesis durability remain excellent in multicenter follow-up through 8 years in a population predominantly older than 60 years at the time of the operation.