异种牛颈静脉带瓣管道重建右室流出道研究

Animal experimental study on acellular, tanned, modified xenogeneic bovine jugular vein conduit reconstruction of right ventricular outflow tract

目的观察去细胞牛颈静脉带瓣管道（BJVC）重建猪右心室流出道后的细胞生长特性、抗钙化性能及血流动力学性能。方法应用经去细胞、鞣制、改性（B组，n=8）及未去细胞（A组，n=8）的BJVC分别进行猪肺动脉与右心室连接，行光镜及电镜观察宿主内皮细胞及肌成纤维细胞生长特点，原子火焰法检测组织钙含量，超声心动图检测BJVC血流动力学参数。结果术前A组BJVC试片表面无内皮细胞，术后12个月内膜表面50％～60％的表面覆盖卵圆形内皮细胞，基质层未见宿主成纤维细胞迁入；术前B组去细胞后BJVC已基本无细胞成分，术后12个月内皮细胞覆盖率约80％～90％，宿主肌成纤维细胞已爬行迁移至基质层的1／3。术后A组近端及远端吻合口管壁、瓣膜组织钙含量显著大于B组（P〈0．05），B组上述各项指标均显著大于新鲜BJVC（P〈0．05）。术后当天A组及B组各项血流动力学指标比较差异无统计学意义（P〉0．05），B组术后当天及术后12月各项指标比较差异无统计学意义（P〉0．05）；术后12月A组远端吻合口口径显著小于B组（P〈0．05），远端吻合口压差、跨瓣压差、牛颈静脉返流量显著大于B组（P〈0．05）。结论去细胞化后鞣制、改性的牛颈静脉是一种更好的重建右室流道材料，但远期效果需进一步研究。

Objective To study the cell growth characteristics, anti-calcification properties and hemodynamic performance of the acellular valved bovine jugular venous conduits （BJVC） after reconstructing pig right ventricular outflow tract. Methods The acellular, tanned, modified （ group B, n = 8 ） and no-acellular （ group A, n = 8 ） BJVC respectively were used to connect porcine pulmonary artery and right ventricle. The growth characteristics of host endothelial cells and myofibroblasts were observed under the light microscopy and electron microscopy. The contents of calcium were detected by atomic flame. BJVC hemodynamic parameters were assessed by echocardiography. Results In group A, preoperative BJVC specimen surface was lined without endothelial cells. At 12th month postoperation, 50%-60% of the surface was covered by endothelial ceils, and no host fibroblasts migrated into matrix. Before operation in group B, the cells of BJVC were basically acellularized. At 12th month postoperation, endothelial cell covered about 80%-90% of specimen surface, and host myofibroblasts migrated into the matrix for 1/3. In group A, calcium contenfly of postoperative proximal and distal anastomotic wall, heart valves were significantly higher than in group B （P 〈 0.05）. In group B, the above indicators were significantiy higher than in the fresh BJVC （P 〈 0. 05）. On the postoperative first day the indicators of hemodynamics in groups A and B showed no statistically significant difference （P 〉 0. 05 ） , and the indicators showed no statistically significant difference （P 〉0. 05） in group B on the postoperative first day and 12th month. The distal anastomosis diameter in group A was significantly smaller than in group B （P 〈 0. 05） on the postoperative 12th month, and distal anastomotic pressure, pressure gradient and bovine jugular vein back flow were significantly greater in group than in group B （P 〈 0.05）. Conclusion The acellular, tanned, modified bo-vine jugular vein is an ideal material for reconstruction of right ventricular flow tract, but the long-term effects need further study.