Department of Cardiothoracic, Transplant and Vascular Surgery, Hannover Medical School, Hannover, Germany.
Eur J Cardiothorac Surg. 2017 Aug 1;52(2):264-271. doi: 10.1093/ejcts/ezx161.
The Mitroflow aortic pericardial bioprosthesis was widely employed in the past. However, some authors have recently reported early structural valve deterioration (SVD) of the Mitroflow LA/LXA model. Thus, we reviewed our experience with the Mitroflow bioprosthesis and studied the risk factors for SVD and mortality.
Records of patients who underwent aortic valve replacement with a Mitroflow bioprosthesis between November 2005 and January 2015 were retrospectively evaluated with Kaplan-Meier, Cox-regression and multistate analysis. Only patients with a complete clinical follow-up were included in the study. Average follow-up was 45 months and ended on 1 April 2016.
Between November 2005 and January 2015, among the 916 patients undergoing aortic valve replacement with the Mitroflow prosthesis at our Institution, the 832 (90.8%) patients with follow-up information were included into the study. Fifty-two (6.2%) patients developed SVD (stenosis, n = 38; regurgitation, n = 7; mixed, n = 7). Freedom from SVD was 95.4% and 67.9%, at 5 and 9 years, respectively, without differences after stratification according to the prosthesis model ( P = 0.87) and prosthesis size ( P = 0.70). At the multivariable analysis, increasing age was identified as a protective factor against SVD (hazard ratio = 0.94, P < 0.001). Twenty (38.4%) patients with SVD underwent redo aortic valve replacement. At 5 and 9 years, survival was 64.5% and 43.1%, repectively. According to the multistate analysis, the fraction of patients living with degenerated valves at 9 years was 10.0%; 7.1% died following degeneration.
The LA/LXA Mitroflow model showed limited long-term durability. Degenerated prostheses showed more stenosis than regurgitation. Patient age played an important role in the development of SVD.
米托罗夫（Mitroflow）心脏生物主动脉瓣假体过去被广泛应用。然而，最近一些作者报告了米托罗夫 LA/LXA 模型的早期结构性瓣膜退化（SVD）。因此，我们回顾了我们使用米托罗夫生物瓣的经验，并研究了 SVD 和死亡率的危险因素。
回顾性评估了 2005 年 11 月至 2015 年 1 月期间接受米托罗夫生物瓣主动脉瓣置换术的患者的病历，采用 Kaplan-Meier、Cox 回归和多状态分析。仅纳入有完整临床随访的患者。平均随访 45 个月，随访结束时间为 2016 年 4 月 1 日。
在我院接受米托罗夫假体主动脉瓣置换术的 916 例患者中，2005 年 11 月至 2015 年 1 月期间，有 832 例（90.8%）患者有随访资料，被纳入研究。52 例（6.2%）患者发生 SVD（狭窄 38 例，反流 7 例，混合 7 例）。5 年和 9 年无 SVD 生存率分别为 95.4%和 67.9%，按假体模型（ P = 0.87）和假体尺寸（ P = 0.70）分层后无差异。多变量分析显示，年龄增加是 SVD 的保护因素（风险比 0.94， P < 0.001）。20 例（38.4%）SVD 患者接受了再次主动脉瓣置换术。5 年和 9 年时，生存率分别为 64.5%和 43.1%。根据多状态分析，9 年时患有退行性瓣膜的患者比例为 10.0%；7.1%的患者死于退行性变。
LA/LXA 米托罗夫模型显示出有限的长期耐用性。退行性瓣膜以狭窄为主，反流较少。患者年龄在 SVD 发生中起重要作用。
