The Freedom Solo pericardial stentless valve: Single-center experience, outcomes, and long-term durability

Objectives: To report our institutional experience and long-term results with the Freedom Solo bovine pericardial stentless bioprosthesis (Sorin Group, Saluggia, Italy). Methods: Between January 2005 and November 2009, 149 patients (mean age, 73.6 +/- 8.7 years; 68 [45.6%] female) underwent isolated (n = 75) or combined (n = 74) aortic valve replacement (AVR) using the Solo in our institution. Followup was 100% complete with an average follow-up time of 5.9 +/- 2.6 years (maximum, 9.6 years) and a total of 885.3 patient years. Results: Operative (30-day) mortality was 2.7%(1.3% for isolated AVR [n = 1] and 4.0% for combined procedures [n = 3]). All causes of death were not valve-related. Preoperative peak (mean) gradients of 74.2 +/- 23.0 mm Hg (48.6 +/- 16.3 mm Hg) decreased to 15.6 +/- 5.4 mm Hg (8.8 +/- 3.0 mm Hg) after AVR, and remained low for up to 9 years. The postoperative effective orifice area was 1.6 +/- 0.57 cm 2, 1.90 +/- 0.45 cm 2, 2.12 +/- 0.48 cm 2, and 2.20 +/- 0.66 cm 2 for the valve sizes 21, 23, 25, and 27, respectively, with absence of severe prosthesis-patient mismatch and 0.7% (n = 1) experienced moderate prosthesis-patient mismatch. During follow-up, 26 patients experienced structural valve deterioration (SVD) and 14 patients underwent explantation. Kaplan-Meier estimates for freedom from death, explantation, and SVD at 9 years averaged 0.57 (range, 0.47-0.66), 0.82 (range, 0.69-0.90), and 0.70 (range, 0.57-0.79), respectively. Conclusions: The Freedom Solo stentless aortic valve is safe to implant and shows excellent early and midterm hemodynamic performance. However, SVD was observed in a substantial number of patients after only 5-6 years and the need for explantation increased markedly, suggesting low durability.