The Freedom SOLO valve: mid-term clinical results with a stentless pericardial valve for aortic valve replacement.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the Freedom SOLO pericardial stentless valve prosthesis implanted in a subcoronary or supra-annular position, using a single running suture, over a follow up period of up to five years. The clinical data obtained after aortic valve replacement (AVR) were analyzed retrospectively for validation. METHODS: Between April 2004 and September 2009, a total of 143 patients (81 males, 62 females; mean age 71 +/- 7 years; range: 41-87 years) underwent primary AVR using the Freedom SOLO valve, implanted with a supra-annular subcoronary technique. Isolated AVR was performed on 120 patients, while 23 patients required additional surgery that included coronary artery bypass grafting (n = 5), ascending aorta replacement (n = 1), atrial fibrillation surgery (n = 9), and mitral valve repair (n = 1). Clinical investigations were performed before, during and after surgery; the follow up was 100% complete. A subgroup of patients (70%) was investigated echocardiographically during the follow up period to analyze the hemodynamic performance of the prosthesis. RESULTS: For all procedures the mean ischemia time was 66 +/- 15 min, and the mean cardiopulmonary bypass (CPB) time 88 +/- 20 min. For isolated AVR, the mean cross-clamp time was 65 +/- 14 min, and the mean CPB time 85 +/- 17 min. The predominant implanted valve size was 25 mm (42%). Operative mortality was 4.9% (7/143), with an overall mortality of 10.5% (15/143) at 4.7 years of follow up. The mean follow up was 1.8 +/- 1.4 years, and the total follow up 257 patient-years. At postoperative follow up the mean valve gradient was 10.6 mmHg, while the effective orifice area was 1.9 +/- 0.6 cm2 at one month and 1.9 +/- 0.6 cm2 at 12 months. CONCLUSION: The Freedom SOLO valve was implanted in a cohort of patients, using a simplified, supra-annular subcoronary technique, with no technical problems. Subsequently, the valve demonstrated an excellent clinical performance for up to five years. Further long-term follow up will be required to confirm the performance of the prosthesis with regards to structural and nonstructural valve stability.