Abstract：
To compare the long-term outcomes of mechanical versus bioprosthetic aortic valve replacement (AVR) in patients aged <50 years, we performed a study-level meta-analysis with reconstructed time-to-event data including studies published by December of 2023. The primary outcome was overall survival. Secondary outcomes included reoperation, major bleeding, and stroke. A total of 5 studies met our inclusion criteria, with a total of 4,245 patients (2,311 mechanical and 1,934 bioprosthetic). All studies were observational and the mean age of groups across the studies ranged from 38.2 to 43.0 years. The median follow-up time was 11.4 years (interquartile range 6.9 to 15.0). Bioprosthetic AVR was associated with reduced overall survival and higher risk of all-cause death (hazard ratio [HR] 1.170 95% confidence interval [CI] 1.002 to 1.364, p = 0.046), increased risk of reoperation over time (HR 2.581, 95% CI 2.102 to 3.168, p <0.001), decreased risk of major bleeding (HR 0.500, 95% CI 0.367 to 0.682, p <0.001), and decreased risk of stroke (HR 0.751, 95% C, 0.565 to 0.998, p = 0.049) compared with mechanical AVR in patients aged <50 years. In conclusion, for patients aged <50 years, bioprosthetic AVR is associated with increased mortality and risk of reoperation compared with mechanical valves. In contrast, mechanical AVR is associated with an increased risk of major bleeding events and stroke. These aspects should be carefully considered during the selection of valve type in this age group; however, we should keep in mind that the statistically significant differences in the risk of all-cause death and stroke might not be clinically relevant (because of marginal statistical significance).
摘要：
为了比较50岁以下患者的机械和生物主动脉瓣置换术（AVR）的长期结果，我们使用重建的事件发生时间数据进行了研究水平的荟萃分析，包括2023年12月发表的研究。主要结果是总生存率。次要结果包括再次手术，大出血,和中风。五项研究符合我们的纳入标准，共有4245例患者（2311例机械性，1934年生物假体）。所有研究都是观察性的，研究中各组的平均年龄为38.2至43.0岁。中位随访时间为11.4年(IQR，6.9-15.0）。生物假体AVR与总生存率降低和全因死亡风险较高相关(HR，1.170[95%CI，1.002-1.364]，P=0.046),随着时间的推移，再次手术的风险增加(HR，2.581，[95%CI，2.102-3.168]，P<0.001)，降低大出血风险(HR，0.500，[95%CI，0.367-0.682]，P<0.001)，和降低中风风险(HR，0.751，[95%CI，0.565-0.998]，P=0.049）与50岁以下患者的机械AVR相比。总之,对于50岁以下的患者,与机械瓣膜相比,生物假体AVR与死亡率和再手术风险增加相关.另一方面,机械性AVR与大出血事件和卒中风险增加相关.在选择该年龄组的阀门类型时，应仔细考虑这些方面；但是，我们应该记住,全因死亡和卒中风险的统计学显著差异可能与临床无关(由于边际统计学意义).
