Klepetko W, Moritz A, Mlczoch J, Schurawitzki H, Domanig E, Wolner E
Second Surgical Department, University of Vienna, Austria.
J Thorac Cardiovasc Surg. 1989 Jan;97(1):90-4.
Two cases of leaflet fracture in the Edwards-Duromedics valve at 36 and 38 months after implantation are reported. Both patients were immediately reoperated on and recovered well. In one valve an older housing fracture with partial tissue ingrowth was noted beside a recent transverse leaflet fracture. In the other valve the leaflet was fractured near the pivot mechanism. All larger embolized parts were detected in the iliac artery region by computed tomographic scan and were subsequently removed. Problems in diagnosis and the importance of immediate reoperation, even without exact diagnosis, are discussed. Technical evaluation of the valve revealed crack growth and arrest, giving evidence of fatigue fracture. Scanning electron microscopic examination revealed several areas of pitting and erosion. Although the exact cause of mechanical disruption remains speculative, pyrolytic carbon seems to have the characteristic of fatigue fracture as well as erosion damage. A connection between the two might exist.
报告了2例植入Edwards-Duromedics瓣膜后36个月和38个月出现瓣叶破裂的病例。两名患者均立即接受再次手术，恢复良好。在一个瓣膜中，除了近期的横向瓣叶破裂外，还发现一个较陈旧的瓣架破裂且有部分组织向内生长。在另一个瓣膜中，瓣叶在枢轴机制附近发生破裂。通过计算机断层扫描在髂动脉区域检测到所有较大的栓塞部分，随后将其取出。文中讨论了诊断方面的问题以及即使没有确切诊断也应立即进行再次手术的重要性。对瓣膜的技术评估显示有裂纹扩展和停滞，证明存在疲劳断裂。扫描电子显微镜检查发现了几个点蚀和侵蚀区域。虽然机械破坏的确切原因仍属推测，但热解碳似乎具有疲劳断裂以及侵蚀损伤的特征。两者之间可能存在联系。
