Lindblom D, Björk V O, Semb B K
J Thorac Cardiovasc Surg. 1986 Nov;92(5):894-907.
The experience after implantation of 3,334 Björk-Shiley valves over a 15 year period is described. With a 99.2% follow-up (covering 17,511 patient-years, mean follow-up time 6.3 years) and an autopsy rate of 75% among all fatalities, altogether 19 cases of mechanical failure were documented. There were no mechanical failures among the standard Delrin Björk-Shiley valve (n = 271), the aortic standard Pyrolyte Björk-Shiley (n = 739), or the Monostrut Björk-Shiley valve (n = 377). One of the mitral standard Pyrolyte valves (n = 430) fractured. Among the 1,461 convexo-concave valves, 18 fractured (6/884 with an opening angle of 60 degrees and 12/577 with an opening angle of 70 degrees). The actuarial incidence of mechanical failure at 5 years was 0.6% (with an upper 95% confidence limit of 1.2%) for the 60 degree convexo-concave valve and 2.8% (upper 95% confidence limit of 4.4%) for the 70 degree convexo-concave valve (p less than 0.01). Two groups of valves were especially affected by this complication; the 23 mm aortic 60 degree convexo-concave valve (5 year actuarial incidence 2.2%, upper 95% confidence limit 4.7%) and the 29 to 31 mm mitral 70 degree convexo-concave valve (8.3%, upper 95% confidence limit 14.2%). The hazard function presently indicates a constant (60 degree convexo-concave) or decreasing (70 degree convexo-concave) tendency for mechanical failure. The time interval between the first symptom of mechanical failure and circulatory collapse was significantly (p less than 0.01) shorter after aortic failure than after mitral failure, and no patient with a fractured aortic prosthesis survived long enough to undergo reoperation. The incidence of mechanical failure among patients dying suddenly (but with an autopsy) was 9.6% (95% confidence limits 4.9%-16.6%), and most cases of sudden death were unrelated to the prosthesis. The management of patients with suspected mechanical failure is described. Prophylactic re-replacements are discussed but cannot be generally recommended at present.
本文描述了15年间植入3334个 Björk-Shiley瓣膜后的经验。随访率为99.2%（涵盖17511患者年，平均随访时间6.3年），所有死亡病例的尸检率为75%，共记录了19例机械故障。标准的聚甲醛 Björk-Shiley瓣膜（n = 271）、主动脉标准热解碳 Björk-Shiley瓣膜（n = 739）或单支柱Björk-Shiley瓣膜（n = 377）均未发生机械故障。一枚二尖瓣标准热解碳瓣膜（n = 430）发生破裂。在1461个凸凹型瓣膜中，有18个发生破裂（开口角度为60度的884个中有6个，开口角度为70度的577个中有12个）。60度凸凹型瓣膜5年时机械故障的精算发生率为0.6%（95%置信上限为1.2%），70度凸凹型瓣膜为2.8%（95%置信上限为4.4%）（p<0.01）。两组瓣膜受此并发症影响尤为明显；23毫米主动脉60度凸凹型瓣膜（5年精算发生率2.2%，95%置信上限4.7%）和29至31毫米二尖瓣70度凸凹型瓣膜（8.3%，95%置信上限14.2%）。目前的风险函数表明机械故障呈恒定（60度凸凹型）或下降（70度凸凹型）趋势。机械故障的首发症状与循环衰竭之间的时间间隔，主动脉故障后明显（p<0.01）短于二尖瓣故障后，且没有主动脉假体破裂的患者存活足够长时间接受再次手术。突然死亡（但接受尸检）患者的机械故障发生率为9.6%（95%置信区间4.9%-16.6%），且大多数猝死病例与假体无关。本文描述了疑似机械故障患者的管理方法。讨论了预防性再次置换，但目前尚不能普遍推荐。
