Bortolotti U, Milano A, Mazzucco A, Guerra F, Stellin G, Talenti E, Thiene G, Gallucci V
Department of Cardiovascular Surgery, University of Padova Medical School, Italy.
Ann Thorac Surg. 1990 Nov;50(5):734-8. doi: 10.1016/0003-4975(90)90673-t.
From March 1979 to December 1984, the Liotta low-profile porcine bioprosthesis was employed for mitral valve replacement in 71 patients to avoid potential left ventricle-prosthesis mismatch occasionally observed with the standard, high-profile, Hancock porcine xenograft. Follow-up of 61 operative survivors showed at 10 years an actuarial survival of 67% +/- 7%, freedom from thromboemboli of 96% +/- 2%, freedom from structural deterioration of 63% +/- 11% and freedom from all Liotta bioprosthesis-related complications of 53% +/- 10%. Complications related to excessive protrusion of the stent into the left ventricular cavity were eliminated with the Liotta bioprosthesis; the peculiar stent configuration, however, was responsible for an increased rate of structural deterioration requiring reoperation in 10 patients (2.8% +/- 0.9%/patient-year) at a mean interval of 76 +/- 18 months after mitral valve replacement (range, 45 to 106 months). Common findings in all explants were cusp prolapse, cusp tears, and commissural rupture related to various degrees of tissue calcification, constantly leading to severe prosthetic incompetence. As also shown experimentally, such structural changes have been attributed to increased systolic stresses on the closed cusps, favored by excessive reduction of the stent height. Our experience shows that the Liotta bioprosthesis used for mitral valve replacement does not provide any clear-cut advantage over standard porcine bioprostheses and that its long-term durability appears affected by the unique prosthetic design.
1979年3月至1984年12月，71例患者采用利奥塔低剖面猪生物瓣膜进行二尖瓣置换术，以避免使用标准的、高剖面的汉考克猪异种移植物时偶尔观察到的潜在左心室-人工瓣膜不匹配。对61例手术幸存者的随访显示，10年时的精算生存率为67%±7%，无血栓栓塞率为96%±2%，无结构恶化率为63%±11%，无所有与利奥塔生物瓣膜相关并发症率为53%±10%。利奥塔生物瓣膜消除了与支架过度突入左心室腔相关的并发症；然而，独特的支架结构导致结构恶化率增加，10例患者（2.8%±0.9%/患者年）需要再次手术，平均间隔时间为二尖瓣置换术后76±18个月（范围45至106个月）。所有取出的人工瓣膜的常见表现为瓣叶脱垂、瓣叶撕裂和与不同程度组织钙化相关的瓣叶联合破裂，持续导致严重的人工瓣膜功能不全。如实验所示，这种结构变化归因于关闭瓣叶上收缩期应力增加，这因支架高度过度降低而加剧。我们的经验表明，用于二尖瓣置换的利奥塔生物瓣膜与标准猪生物瓣膜相比没有明显优势，其长期耐久性似乎受到独特人工瓣膜设计的影响。
