The Late Impact of Surgical Skills and Training on the Subcoronary Implantation of the Freestyle Stentless Bioprosthesis

作者：Albert Alexander^*; Florath Ines; Rosendahl Ulrich; Ismail Mohamed; Hassanein Wael; Ennker Juergen

来源：Journal of Heart Valve Disease, 2010, 19(1): 104-114.

Background and aim of the study: Recent data have demonstrated an impact of higher postoperative mean pressure gradient (MPG) across the subcoronary Freestyle stentless bioprosthesis on the mid-term quality of life, but not on that of survival. Thus, the question remains that, with a prolonged follow up, would an effect on duration of survival also evolve?
Methods: Between 1996 and 2006, a total of 939 patients underwent aortic valve replacement (AVR) for aortic stenosis with the Freestyle stentless bioprosthesis, using the subcoronary technique. A follow up was conducted by mailed questionnaires, and completed by telephone interviews in September 2008. The follow up was 99% complete and totaled 3,468 patient-years (pt-yr); the mean follow up time was 7.7 years (range: 7.3-8.1 years). The maximum follow up was 11.9 years.
Results: Actuarial survival rates at five and 10 years were 73 +/- 2% and 35 +/- 4%, respectively. The cut-off gradient was identified at a postoperative MPG of 20 mmHg, where a gradient >20 mmHg had a negative impact on survival rate (p = 0.008), as indicated by the greatest fall of deviance in the Akaike information criterion. Risk factors also affecting survival rate included atrial fibrillation, diabetes, higher serum creatinine levels, greater age, left ventricular ejection fraction <= 40%, liver insufficiency, lower body mass index, chronic obstructive pulmonary disease, and peripheral arterial disease. Risk factors for MPG >20 mmHg were a smaller valve size, a higher preoperative gradient, individual surgeons and lesser cumulative experience, and early adopters (surgeons) of the subcoronary stentless valve implantation technique.
Conclusion: A higher MPG impedes long-term survival, with the cut-off being at 20 mmHg. A higher MPG was largely influenced by the individual surgeons and their cumulative experience of using the subcoronary technique. Late adopters of the technique profited from the observations of early adopters. The standardization of a surgical technique and the identification of common pitfalls were key to optimizing the surgical outcome after stentless valve implantation.

• 出版日期2010-1